blocks|key|606792|text|++public+static+bool+IsPropertyExist(dynamic+settings,+string+name)
++{
++++if+(settings+is+ExpandoObject)
++++++return+((IDictionary<string,+object>)settings).ContainsKey(name);

++++return+settings.GetType().GetProperty(name)+!=+null;
++}

++var+settings+=+new+{Filename+=+@"c:\temp\q.txt"};
++Console.WriteLine(IsPropertyExist(settings,+"Filename"));
++Console.WriteLine(IsPropertyExist(settings,+"Size"));|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|606793|输出：|unstyled|606794|+True
+False|606795|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|L|8|@]|9|@]|A|$]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$B|C]]|$1|I|3|-4|5|F|7|N|8|@]|9|@]|A|$]]]|J|$]]

<pre><code> public static bool IsPropertyExist(dynamic settings, string name)
 {
 if (settings is ExpandoObject)
 return ((IDictionary&lt;string, object&gt;)settings).ContainsKey(name);

 return settings.GetType().GetProperty(name) != null;
 }

 var settings = new {Filename = @"c:\temp\q.txt"};
 Console.WriteLine(IsPropertyExist(settings, "Filename"));
 Console.WriteLine(IsPropertyExist(settings, "Size"));
</code></pre>

Output:

<pre><code> True
 False
</code></pre>

blocks|key|606812|text|public+static+bool+HasProperty(dynamic+obj,+string+name)
{
++++Type+objType+=+obj.GetType();

++++if+(objType+==+typeof(ExpandoObject))
++++{
++++++++return+((IDictionary<string,+object>)obj).ContainsKey(name);
++++}

++++return+objType.GetProperty(name)+!=+null;
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|606813|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>public static bool HasProperty(dynamic obj, string name)
{
 Type objType = obj.GetType();

 if (objType == typeof(ExpandoObject))
 {
 return ((IDictionary&lt;string, object&gt;)obj).ContainsKey(name);
 }

 return objType.GetProperty(name) != null;
}
</code></pre>

blocks|key|606778|text|如果您可以控制设置对象的创建/传递，我建议您使用ExpandoObject。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|606779|dynamic+settings+=+new+ExpandoObject();
settings.Filename+=+"asdf.txt";
settings.Size+=+10;
...

function+void+Settings(dynamic+settings)
{
++++if+(+((IDictionary<string,+object>)settings).ContainsKey("Filename")+)
++++++++....+do+something+....
}|code-block|syntax|javascript|606780|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

if you can control creating/passing the settings object, i'd recommend using an ExpandoObject instead.

<pre><code>dynamic settings = new ExpandoObject();
settings.Filename = "asdf.txt";
settings.Size = 10;
...

function void Settings(dynamic settings)
{
 if ( ((IDictionary&lt;string, object&gt;)settings).ContainsKey("Filename") )
 .... do something ....
}
</code></pre>

blocks|key|607353|text|这适用于匿名类型、ExpandoObject、Nancy.DynamicDictionary或任何可以转换为IDictionary<string,+object>的类型。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|607354|++++public+static+bool+PropertyExists(dynamic+obj,+string+name)+{
++++++++if+(obj+==+null)+return+false;
++++++++if+(obj+is+IDictionary<string,+object>+dict)+{
++++++++++++return+dict.ContainsKey(name);
++++++++}
++++++++return+obj.GetType().GetProperty(name)+!=+null;
++++}|code-block|syntax|javascript|607355|entityMap^0|9|D|N|N|1I|R|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|U|8|@]|D|@]|E|$]]]|L|$]]

This works for anonymous types, <code>ExpandoObject</code>, <code>Nancy.DynamicDictionary</code> or anything else that can be cast to <code>IDictionary&lt;string, object&gt;</code>.

<pre><code> public static bool PropertyExists(dynamic obj, string name) {
 if (obj == null) return false;
 if (obj is IDictionary&lt;string, object&gt; dict) {
 return dict.ContainsKey(name);
 }
 return obj.GetType().GetProperty(name) != null;
 }
</code></pre>

blocks|key|390725|text|这对我很有效--|type|unstyled|depth|inlineStyleRanges|entityRanges|data|390726|++public+static+bool+IsPropertyExist(dynamic+dynamicObj,+string+property)
+++++++{
+++++++++++try
+++++++++++{
+++++++++++++++var+value=dynamicObj[property].Value;
+++++++++++++++return+true;
+++++++++++}
+++++++++++catch+(RuntimeBinderException)
+++++++++++{

+++++++++++++++return+false;
+++++++++++}

+++++++}|code-block|syntax|javascript|390727|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

This is working for me-:

<pre><code> public static bool IsPropertyExist(dynamic dynamicObj, string property)
 {
 try
 {
 var value=dynamicObj[property].Value;
 return true;
 }
 catch (RuntimeBinderException)
 {

 return false;
 }

 }
</code></pre>

blocks|key|391016|text|合并和修复来自Serj-TM和user3359453的答案，以便它可以与ExpandoObject和DynamicJsonObject一起工作。这对我很有效。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|391017|public+static+bool+HasPropertyExist(dynamic+settings,+string+name)
{
++++if+(settings+is+System.Dynamic.ExpandoObject)
++++++++return+((IDictionary<string,+object>)settings).ContainsKey(name);

++++if+(settings+is+System.Web.Helpers.DynamicJsonObject)
++++try
++++{
++++++++return+settings[name]+!=+null;
++++}
++++catch+(KeyNotFoundException)
++++{
++++++++return+false;
++++}


++++return+settings.GetType().GetProperty(name)+!=+null;
}|code-block|syntax|javascript|391018|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Merging and fixing answers from Serj-TM and user3359453 so that it works with both ExpandoObject and DynamicJsonObject. This works for me.

<pre><code>public static bool HasPropertyExist(dynamic settings, string name)
{
 if (settings is System.Dynamic.ExpandoObject)
 return ((IDictionary&lt;string, object&gt;)settings).ContainsKey(name);

 if (settings is System.Web.Helpers.DynamicJsonObject)
 try
 {
 return settings[name] != null;
 }
 catch (KeyNotFoundException)
 {
 return false;
 }


 return settings.GetType().GetProperty(name) != null;
}
</code></pre>

blocks|key|606932|text|使用反射，这是我使用的函数：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|606933|public+static+bool+doesPropertyExist(dynamic+obj,+string+property)
{
++++return+((Type)obj.GetType()).GetProperties().Where(p+=>+p.Name.Equals(property)).Any();
}|code-block|syntax|javascript|606934|然后..。|606935|if+(doesPropertyExist(myDynamicObject,+"myProperty")){
++++//+...
}|606936|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Using reflection, this is the function i use :

<pre><code>public static bool doesPropertyExist(dynamic obj, string property)
{
 return ((Type)obj.GetType()).GetProperties().Where(p =&gt; p.Name.Equals(property)).Any();
}
</code></pre>

then..

<pre><code>if (doesPropertyExist(myDynamicObject, "myProperty")){
 // ...
}
</code></pre>

blocks|key|607592|text|我遇到的是动态的Newtonsoft.Json.Linq.JObject而不是IDictionary|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|607593|我添加了和额外的if，它起作用了。|607594|public+static+bool+PropertyExists(dynamic+obj,+string+name)
{
++++if+(obj+==+null)+return+false;

++++else+if+(obj+is+IDictionary<string,+object>+dict)
++++{
++++++++return+dict.ContainsKey(name);
++++}

++++else+if+(obj+is+Newtonsoft.Json.Linq.JObject+jObject)
++++{
++++++++return+jObject.ContainsKey(name);
++++}

++++else
++++{
++++++++return+obj.GetType().GetProperty(name)+!=+null;
++++}
}|code-block|syntax|javascript|607595|entityMap^0|8|S|13|B|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|T|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|U|8|@]|D|@]|E|$K|L]]|$1|M|3|-4|5|6|7|V|8|@]|D|@]|E|$]]]|N|$]]

I ran into the dynamic was <code>Newtonsoft.Json.Linq.JObject</code> instead of <code>IDictionary</code>
I added and extra if and it works.
<pre><code>public static bool PropertyExists(dynamic obj, string name)
{
 if (obj == null) return false;

 else if (obj is IDictionary&lt;string, object&gt; dict)
 {
 return dict.ContainsKey(name);
 }

 else if (obj is Newtonsoft.Json.Linq.JObject jObject)
 {
 return jObject.ContainsKey(name);
 }

 else
 {
 return obj.GetType().GetProperty(name) != null;
 }
}
</code></pre>

blocks|key|390968|text|上面的解决方案都不适用于来自Json的dynamic，但是我设法用Try+catch+(由@user3359453编写)将抛出的异常类型(KeyNotFoundException而不是RuntimeBinderException)转换为实际有效的异常类型……|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|390969|public+static+bool+HasProperty(dynamic+obj,+string+name)
++++{
++++++++try
++++++++{
++++++++++++var+value+=+obj[name];
++++++++++++return+true;
++++++++}
++++++++catch+(KeyNotFoundException)
++++++++{
++++++++++++return+false;
++++++++}
++++}|code-block|syntax|javascript|390970|​|390971|📷|atomic|390972|390973|希望这能节省你的时间。|390974|entityMap|0|IMAGE|mutability|IMMUTABLE|imageUrl|https://ask.qcloudimg.com/http-save/yehe-900000/f190d4846292f82a43d3baf880b488f2.png|imageAlt^0|E|4|J|7|X|9|1X|K|2K|M|0|0|0|0|1|0|0|0|0^^$0|@$1|2|3|4|5|6|7|11|8|@$9|12|A|13|B|C]|$9|14|A|15|B|C]|$9|16|A|17|B|C]|$9|18|A|19|B|C]|$9|1A|A|1B|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|1C|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|1D|8|@]|D|@]|E|$]]|$1|M|3|N|5|O|7|1E|8|@]|D|@$9|1F|A|1G|1|1H]]|E|$]]|$1|P|3|L|5|6|7|1I|8|@]|D|@]|E|$]]|$1|Q|3|R|5|6|7|1J|8|@]|D|@]|E|$]]|$1|S|3|-4|5|6|7|1K|8|@]|D|@]|E|$]]]|T|$U|$5|V|W|X|E|$Y|Z|10|-4]]]]

None of the solutions above worked for <code>dynamic</code> that comes from <code>Json</code>, I however managed to transform one with <code>Try catch</code> (by @user3359453) by changing exception type thrown (<code>KeyNotFoundException</code> instead of <code>RuntimeBinderException</code>) into something that actually works... 

<pre><code>public static bool HasProperty(dynamic obj, string name)
 {
 try
 {
 var value = obj[name];
 return true;
 }
 catch (KeyNotFoundException)
 {
 return false;
 }
 }
</code></pre>

<a href="https://i.stack.imgur.com/XFHpb.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/XFHpb.png" alt="enter image description here"></a>

Hope this saves you some time.

blocks|key|607381|text|如果有人需要处理来自Json的动态对象，我已经修改了Seth+Reno+answer来处理从NewtonSoft.Json.JObjcet反序列化的动态对象。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|607382|public+static+bool+PropertyExists(dynamic+obj,+string+name)
++++{
++++++++if+(obj+==+null)+return+false;
++++++++if+(obj+is+ExpandoObject)
++++++++++++return+((IDictionary<string,+object>)obj).ContainsKey(name);
++++++++if+(obj+is+IDictionary<string,+object>+dict1)
++++++++++++return+dict1.ContainsKey(name);
++++++++if+(obj+is+IDictionary<string,+JToken>+dict2)
++++++++++++return+dict2.ContainsKey(name);
++++++++return+obj.GetType().GetProperty(name)+!=+null;
++++}|code-block|syntax|javascript|607383|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

In case someone need to handle a dynamic object come from Json, I has modified Seth Reno answer to handle dynamic object deserialized from NewtonSoft.Json.JObjcet.

<pre><code>public static bool PropertyExists(dynamic obj, string name)
 {
 if (obj == null) return false;
 if (obj is ExpandoObject)
 return ((IDictionary&lt;string, object&gt;)obj).ContainsKey(name);
 if (obj is IDictionary&lt;string, object&gt; dict1)
 return dict1.ContainsKey(name);
 if (obj is IDictionary&lt;string, JToken&gt; dict2)
 return dict2.ContainsKey(name);
 return obj.GetType().GetProperty(name) != null;
 }
</code></pre>

blocks|key|607415|text|为了扩展@Kuroro的答案，如果你需要测试属性是否为空，下面应该可以。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|607416|public+static+bool+PropertyExistsAndIsNotNull(dynamic+obj,+string+name)
{
++++if+(obj+==+null)+return+false;
++++if+(obj+is+ExpandoObject)
++++{
++++++++if+(((IDictionary<string,+object>)obj).ContainsKey(name))
++++++++++++return+((IDictionary<string,+object>)obj)[name]+!=+null;
++++++++return+false;
++++}
++++if+(obj+is+IDictionary<string,+object>+dict1)
++++{
++++++++if+(dict1.ContainsKey(name))
++++++++++++return+dict1[name]+!=+null;
++++++++return+false;
++++}
++++if+(obj+is+IDictionary<string,+JToken>+dict2)
++++{
++++++++if+(dict2.ContainsKey(name))
++++++++++++return+(dict2[name].Type+!=+JTokenType.Null+&&+dict2[name].Type+!=+JTokenType.Undefined);
++++++++return+false;
++++}
++++if+(obj.GetType().GetProperty(name)+!=+null)
++++++++return+obj.GetType().GetProperty(name).GetValue(obj)+!=+null;
++++return+false;
}|code-block|syntax|javascript|607417|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

To extend the answer from @Kuroro, if you need to test if the property is empty, below should work.

<pre><code>public static bool PropertyExistsAndIsNotNull(dynamic obj, string name)
{
 if (obj == null) return false;
 if (obj is ExpandoObject)
 {
 if (((IDictionary&lt;string, object&gt;)obj).ContainsKey(name))
 return ((IDictionary&lt;string, object&gt;)obj)[name] != null;
 return false;
 }
 if (obj is IDictionary&lt;string, object&gt; dict1)
 {
 if (dict1.ContainsKey(name))
 return dict1[name] != null;
 return false;
 }
 if (obj is IDictionary&lt;string, JToken&gt; dict2)
 {
 if (dict2.ContainsKey(name))
 return (dict2[name].Type != JTokenType.Null &amp;&amp; dict2[name].Type != JTokenType.Undefined);
 return false;
 }
 if (obj.GetType().GetProperty(name) != null)
 return obj.GetType().GetProperty(name).GetValue(obj) != null;
 return false;
}
</code></pre>

blocks|key|607453|text|这也适用于DynamicJsonObject：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|607454|++public+static+bool+PropertyExists(dynamic+settings,+string+name)
++{
++++if+(settings+is+ExpandoObject)
++++++return+((IDictionary<string,+object>)settings).ContainsKey(name);
++++else+if+(settings+is+DynamicJsonObject)
++++++return+((DynamicJsonObject)settings).GetDynamicMemberNames().Contains(name);

++++return+settings.GetType().GetProperty(name)+!=+null;
++}|code-block|syntax|javascript|607455|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

This works also for DynamicJsonObject:
<pre><code> public static bool PropertyExists(dynamic settings, string name)
 {
 if (settings is ExpandoObject)
 return ((IDictionary&lt;string, object&gt;)settings).ContainsKey(name);
 else if (settings is DynamicJsonObject)
 return ((DynamicJsonObject)settings).GetDynamicMemberNames().Contains(name);

 return settings.GetType().GetProperty(name) != null;
 }
</code></pre>

blocks|key|607531|text|++++public+static+void+Test()
++++{
++++++++int+LOOP_LENGTH+=+100000000;
++++++++{
++++++++++++long+first_memory+=+GC.GetTotalMemory(true);
++++++++++++var+stopWatch+=+Stopwatch.StartNew();

++++++++++++Console.WriteLine("doesPropertyExist");

++++++++++++dynamic+testdo+=+new+{+A+=+1,+B+=+(string)null,+C+=+"A"+};
++++++++++++for+(int+i+=+0;+i+<+LOOP_LENGTH;+i%2B%2B)
++++++++++++{
++++++++++++++++if+(!TestDynamic.doesPropertyExist(testdo,+"A"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+find");
++++++++++++++++++++break;
++++++++++++++++}

++++++++++++++++if+(TestDynamic.doesPropertyExist(testdo,+"ABC"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+not+find");
++++++++++++++++++++break;
++++++++++++++++}
++++++++++++}
++++++++++++stopWatch.Stop();
++++++++++++var+last_memory+=+GC.GetTotalMemory(true);
++++++++++++Console.WriteLine($"+Time:{stopWatch.Elapsed.TotalSeconds}s\t+Memory:{last_memory+-+first_memory}");
++++++++}

++++++++{
++++++++++++long+first_memory+=+GC.GetTotalMemory(true);
++++++++++++var+stopWatch+=+Stopwatch.StartNew();

++++++++++++Console.WriteLine("HasProperty");

++++++++++++dynamic+testdo+=+new+{+A+=+1,+B+=+(string)null,+C+=+"A"+};
++++++++++++for+(int+i+=+0;+i+<+LOOP_LENGTH;+i%2B%2B)
++++++++++++{
++++++++++++++++if+(!TestDynamic.HasProperty(testdo,+"A"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+find");
++++++++++++++++++++break;
++++++++++++++++}

++++++++++++++++if+(TestDynamic.HasProperty(testdo,+"ABC"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+not+find");
++++++++++++++++++++break;
++++++++++++++++}
++++++++++++}
++++++++++++stopWatch.Stop();
++++++++++++var+last_memory+=+GC.GetTotalMemory(true);
++++++++++++Console.WriteLine($"+Time:{stopWatch.Elapsed.TotalSeconds}s\t+Memory:{last_memory+-+first_memory}");
++++++++}


++++++++{
++++++++++++long+first_memory+=+GC.GetTotalMemory(true);
++++++++++++var+stopWatch+=+Stopwatch.StartNew();

++++++++++++Console.WriteLine("IsPropertyExist");

++++++++++++dynamic+testdo+=+new+{+A+=+1,+B+=+(string)null,+C+=+"A"+};
++++++++++++for+(int+i+=+0;+i+<+LOOP_LENGTH;+i%2B%2B)
++++++++++++{
++++++++++++++++if+(!TestDynamic.IsPropertyExist(testdo,+"A"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+find");
++++++++++++++++++++break;
++++++++++++++++}

++++++++++++++++if+(TestDynamic.IsPropertyExist(testdo,+"ABC"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+not+find");
++++++++++++++++++++break;
++++++++++++++++}
++++++++++++}
++++++++++++stopWatch.Stop();
++++++++++++var+last_memory+=+GC.GetTotalMemory(true);
++++++++++++Console.WriteLine($"+Time:{stopWatch.Elapsed.TotalSeconds}s\t+Memory:{last_memory+-+first_memory}");
++++++++}

++++++++{
++++++++++++long+first_memory+=+GC.GetTotalMemory(true);
++++++++++++var+stopWatch+=+Stopwatch.StartNew();

++++++++++++Console.WriteLine("IsPropertyExistBinderException");

++++++++++++dynamic+testdo+=+new+{+A+=+1,+B+=+(string)null,+C+=+"A"+};
++++++++++++for+(int+i+=+0;+i+<+LOOP_LENGTH;+i%2B%2B)
++++++++++++{
++++++++++++++++if+(!TestDynamic.IsPropertyExistBinderException(testdo,+"A"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+find");
++++++++++++++++++++break;
++++++++++++++++}

++++++++++++++++if+(TestDynamic.IsPropertyExistBinderException(testdo,+"ABC"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+not+find");
++++++++++++++++++++break;
++++++++++++++++}
++++++++++++}
++++++++++++stopWatch.Stop();
++++++++++++var+last_memory+=+GC.GetTotalMemory(true);
++++++++++++Console.WriteLine($"+Time:{stopWatch.Elapsed.TotalSeconds}s\t+Memory:{last_memory+-+first_memory}");
++++++++}


++++++++{
++++++++++++long+first_memory+=+GC.GetTotalMemory(true);
++++++++++++var+stopWatch+=+Stopwatch.StartNew();

++++++++++++Console.WriteLine("PropertyExists");

++++++++++++dynamic+testdo+=+new+{+A+=+1,+B+=+(string)null,+C+=+"A"+};
++++++++++++for+(int+i+=+0;+i+<+LOOP_LENGTH;+i%2B%2B)
++++++++++++{
++++++++++++++++if+(!TestDynamic.PropertyExists(testdo,+"A"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+find");
++++++++++++++++++++break;
++++++++++++++++}

++++++++++++++++if+(TestDynamic.PropertyExists(testdo,+"ABC"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+not+find");
++++++++++++++++++++break;
++++++++++++++++}
++++++++++++}
++++++++++++stopWatch.Stop();
++++++++++++var+last_memory+=+GC.GetTotalMemory(true);
++++++++++++Console.WriteLine($"+Time:{stopWatch.Elapsed.TotalSeconds}s\t+Memory:{last_memory+-+first_memory}");
++++++++}


++++++++{
++++++++++++long+first_memory+=+GC.GetTotalMemory(true);
++++++++++++var+stopWatch+=+Stopwatch.StartNew();

++++++++++++Console.WriteLine("PropertyExistsJToken");

++++++++++++dynamic+testdo+=+new+{+A+=+1,+B+=+(string)null,+C+=+"A"+};
++++++++++++for+(int+i+=+0;+i+<+LOOP_LENGTH;+i%2B%2B)
++++++++++++{
++++++++++++++++if+(!TestDynamic.PropertyExistsJToken(testdo,+"A"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+find");
++++++++++++++++++++break;
++++++++++++++++}

++++++++++++++++if+(TestDynamic.PropertyExistsJToken(testdo,+"ABC"))
++++++++++++++++{
++++++++++++++++++++Console.WriteLine("throw+not+find");
++++++++++++++++++++break;
++++++++++++++++}
++++++++++++}
++++++++++++stopWatch.Stop();
++++++++++++var+last_memory+=+GC.GetTotalMemory(true);
++++++++++++Console.WriteLine($"+Time:{stopWatch.Elapsed.TotalSeconds}s\t+Memory:{last_memory+-+first_memory}");
++++++++}




++++}

++++public+static+bool+IsPropertyExist(dynamic+settings,+string+name)
++++{
++++++++if+(settings+is+ExpandoObject)
++++++++++++return+((IDictionary<string,+object>)settings).ContainsKey(name);

++++++++return+settings.GetType().GetProperty(name)+!=+null;
++++}

++++public+static+bool+HasProperty(dynamic+obj,+string+name)
++++{
++++++++Type+objType+=+obj.GetType();

++++++++if+(objType+==+typeof(ExpandoObject))
++++++++{
++++++++++++return+((IDictionary<string,+object>)obj).ContainsKey(name);
++++++++}

++++++++return+objType.GetProperty(name)+!=+null;
++++}


++++public+static+bool+PropertyExists(dynamic+obj,+string+name)
++++{
++++++++if+(obj+==+null)+return+false;
++++++++if+(obj+is+IDictionary<string,+object>+dict)
++++++++{
++++++++++++return+dict.ContainsKey(name);
++++++++}
++++++++return+obj.GetType().GetProperty(name)+!=+null;
++++}

++++//+public+static+bool+HasPropertyExist(dynamic+settings,+string+name)
++++//+{
++++//+++++if+(settings+is+System.Dynamic.ExpandoObject)
++++//+++++++++return+((IDictionary<string,+object>)settings).ContainsKey(name);
++++//+++++if+(settings+is+DynamicJsonObject)
++++//+++++++++try
++++//+++++++++{
++++//+++++++++++++return+settings[name]+!=+null;
++++//+++++++++}
++++//+++++++++catch+(KeyNotFoundException)
++++//+++++++++{
++++//+++++++++++++return+false;
++++//+++++++++}
++++//+++++return+settings.GetType().GetProperty(name)+!=+null;
++++//+}

++++public+static+bool+IsPropertyExistBinderException(dynamic+dynamicObj,+string+property)
++++{
++++++++try
++++++++{
++++++++++++var+value+=+dynamicObj[property].Value;
++++++++++++return+true;
++++++++}
++++++++catch+(RuntimeBinderException)
++++++++{

++++++++++++return+false;
++++++++}

++++}

++++public+static+bool+HasPropertyFoundException(dynamic+obj,+string+name)
++++{
++++++++try
++++++++{
++++++++++++var+value+=+obj[name];
++++++++++++return+true;
++++++++}
++++++++catch+(KeyNotFoundException)
++++++++{
++++++++++++return+false;
++++++++}
++++}


++++public+static+bool+doesPropertyExist(dynamic+obj,+string+property)
++++{
++++++++return+((Type)obj.GetType()).GetProperties().Where(p+=>+p.Name.Equals(property)).Any();
++++}

++++public+static+bool+PropertyExistsJToken(dynamic+obj,+string+name)
++++{
++++++++if+(obj+==+null)+return+false;
++++++++if+(obj+is+ExpandoObject)
++++++++++++return+((IDictionary<string,+object>)obj).ContainsKey(name);
++++++++if+(obj+is+IDictionary<string,+object>+dict1)
++++++++++++return+dict1.ContainsKey(name);
++++++++if+(obj+is+IDictionary<string,+JToken>+dict2)
++++++++++++return+dict2.ContainsKey(name);
++++++++return+obj.GetType().GetProperty(name)+!=+null;
++++}

++++//+public+static+bool+PropertyExistsJsonObject(dynamic+settings,+string+name)
++++//+{
++++//+++++if+(settings+is+ExpandoObject)
++++//+++++++++return+((IDictionary<string,+object>)settings).ContainsKey(name);
++++//+++++else+if+(settings+is+DynamicJsonObject)
++++//+++++++++return+((DynamicJsonObject)settings).GetDynamicMemberNames().Contains(name);

++++//+++++return+settings.GetType().GetProperty(name)+!=+null;
++++//+}
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|607532|doesPropertyExist|unstyled|607533|时间:59.5907507s内存:403680|607534|HasProperty|607535|时间:30.8231781s内存:14968|607536|IsPropertyExist|607537|时间:39.6179575s内存:97000|607538|IsPropertyExistBinderException抛出查找|607539|PropertyExists|607540|时间:56.009761s内存:13464|607541|PropertyExistsJToken|607542|时间:61.6146953s内存:15952|607543|entityMap^0|0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|12|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|13|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|14|8|@]|9|@]|A|$]]|$1|I|3|J|5|F|7|15|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|16|8|@]|9|@]|A|$]]|$1|M|3|N|5|F|7|17|8|@]|9|@]|A|$]]|$1|O|3|P|5|F|7|18|8|@]|9|@]|A|$]]|$1|Q|3|R|5|F|7|19|8|@]|9|@]|A|$]]|$1|S|3|T|5|F|7|1A|8|@]|9|@]|A|$]]|$1|U|3|V|5|F|7|1B|8|@]|9|@]|A|$]]|$1|W|3|X|5|F|7|1C|8|@]|9|@]|A|$]]|$1|Y|3|Z|5|F|7|1D|8|@]|9|@]|A|$]]|$1|10|3|-4|5|F|7|1E|8|@]|9|@]|A|$]]]|11|$]]

<pre><code> public static void Test()
 {
 int LOOP_LENGTH = 100000000;
 {
 long first_memory = GC.GetTotalMemory(true);
 var stopWatch = Stopwatch.StartNew();

 Console.WriteLine(&quot;doesPropertyExist&quot;);

 dynamic testdo = new { A = 1, B = (string)null, C = &quot;A&quot; };
 for (int i = 0; i &lt; LOOP_LENGTH; i++)
 {
 if (!TestDynamic.doesPropertyExist(testdo, &quot;A&quot;))
 {
 Console.WriteLine(&quot;throw find&quot;);
 break;
 }

 if (TestDynamic.doesPropertyExist(testdo, &quot;ABC&quot;))
 {
 Console.WriteLine(&quot;throw not find&quot;);
 break;
 }
 }
 stopWatch.Stop();
 var last_memory = GC.GetTotalMemory(true);
 Console.WriteLine($&quot; Time:{stopWatch.Elapsed.TotalSeconds}s\t Memory:{last_memory - first_memory}&quot;);
 }

 {
 long first_memory = GC.GetTotalMemory(true);
 var stopWatch = Stopwatch.StartNew();

 Console.WriteLine(&quot;HasProperty&quot;);

 dynamic testdo = new { A = 1, B = (string)null, C = &quot;A&quot; };
 for (int i = 0; i &lt; LOOP_LENGTH; i++)
 {
 if (!TestDynamic.HasProperty(testdo, &quot;A&quot;))
 {
 Console.WriteLine(&quot;throw find&quot;);
 break;
 }

 if (TestDynamic.HasProperty(testdo, &quot;ABC&quot;))
 {
 Console.WriteLine(&quot;throw not find&quot;);
 break;
 }
 }
 stopWatch.Stop();
 var last_memory = GC.GetTotalMemory(true);
 Console.WriteLine($&quot; Time:{stopWatch.Elapsed.TotalSeconds}s\t Memory:{last_memory - first_memory}&quot;);
 }


 {
 long first_memory = GC.GetTotalMemory(true);
 var stopWatch = Stopwatch.StartNew();

 Console.WriteLine(&quot;IsPropertyExist&quot;);

 dynamic testdo = new { A = 1, B = (string)null, C = &quot;A&quot; };
 for (int i = 0; i &lt; LOOP_LENGTH; i++)
 {
 if (!TestDynamic.IsPropertyExist(testdo, &quot;A&quot;))
 {
 Console.WriteLine(&quot;throw find&quot;);
 break;
 }

 if (TestDynamic.IsPropertyExist(testdo, &quot;ABC&quot;))
 {
 Console.WriteLine(&quot;throw not find&quot;);
 break;
 }
 }
 stopWatch.Stop();
 var last_memory = GC.GetTotalMemory(true);
 Console.WriteLine($&quot; Time:{stopWatch.Elapsed.TotalSeconds}s\t Memory:{last_memory - first_memory}&quot;);
 }

 {
 long first_memory = GC.GetTotalMemory(true);
 var stopWatch = Stopwatch.StartNew();

 Console.WriteLine(&quot;IsPropertyExistBinderException&quot;);

 dynamic testdo = new { A = 1, B = (string)null, C = &quot;A&quot; };
 for (int i = 0; i &lt; LOOP_LENGTH; i++)
 {
 if (!TestDynamic.IsPropertyExistBinderException(testdo, &quot;A&quot;))
 {
 Console.WriteLine(&quot;throw find&quot;);
 break;
 }

 if (TestDynamic.IsPropertyExistBinderException(testdo, &quot;ABC&quot;))
 {
 Console.WriteLine(&quot;throw not find&quot;);
 break;
 }
 }
 stopWatch.Stop();
 var last_memory = GC.GetTotalMemory(true);
 Console.WriteLine($&quot; Time:{stopWatch.Elapsed.TotalSeconds}s\t Memory:{last_memory - first_memory}&quot;);
 }


 {
 long first_memory = GC.GetTotalMemory(true);
 var stopWatch = Stopwatch.StartNew();

 Console.WriteLine(&quot;PropertyExists&quot;);

 dynamic testdo = new { A = 1, B = (string)null, C = &quot;A&quot; };
 for (int i = 0; i &lt; LOOP_LENGTH; i++)
 {
 if (!TestDynamic.PropertyExists(testdo, &quot;A&quot;))
 {
 Console.WriteLine(&quot;throw find&quot;);
 break;
 }

 if (TestDynamic.PropertyExists(testdo, &quot;ABC&quot;))
 {
 Console.WriteLine(&quot;throw not find&quot;);
 break;
 }
 }
 stopWatch.Stop();
 var last_memory = GC.GetTotalMemory(true);
 Console.WriteLine($&quot; Time:{stopWatch.Elapsed.TotalSeconds}s\t Memory:{last_memory - first_memory}&quot;);
 }


 {
 long first_memory = GC.GetTotalMemory(true);
 var stopWatch = Stopwatch.StartNew();

 Console.WriteLine(&quot;PropertyExistsJToken&quot;);

 dynamic testdo = new { A = 1, B = (string)null, C = &quot;A&quot; };
 for (int i = 0; i &lt; LOOP_LENGTH; i++)
 {
 if (!TestDynamic.PropertyExistsJToken(testdo, &quot;A&quot;))
 {
 Console.WriteLine(&quot;throw find&quot;);
 break;
 }

 if (TestDynamic.PropertyExistsJToken(testdo, &quot;ABC&quot;))
 {
 Console.WriteLine(&quot;throw not find&quot;);
 break;
 }
 }
 stopWatch.Stop();
 var last_memory = GC.GetTotalMemory(true);
 Console.WriteLine($&quot; Time:{stopWatch.Elapsed.TotalSeconds}s\t Memory:{last_memory - first_memory}&quot;);
 }




 }

 public static bool IsPropertyExist(dynamic settings, string name)
 {
 if (settings is ExpandoObject)
 return ((IDictionary&lt;string, object&gt;)settings).ContainsKey(name);

 return settings.GetType().GetProperty(name) != null;
 }

 public static bool HasProperty(dynamic obj, string name)
 {
 Type objType = obj.GetType();

 if (objType == typeof(ExpandoObject))
 {
 return ((IDictionary&lt;string, object&gt;)obj).ContainsKey(name);
 }

 return objType.GetProperty(name) != null;
 }


 public static bool PropertyExists(dynamic obj, string name)
 {
 if (obj == null) return false;
 if (obj is IDictionary&lt;string, object&gt; dict)
 {
 return dict.ContainsKey(name);
 }
 return obj.GetType().GetProperty(name) != null;
 }

 // public static bool HasPropertyExist(dynamic settings, string name)
 // {
 // if (settings is System.Dynamic.ExpandoObject)
 // return ((IDictionary&lt;string, object&gt;)settings).ContainsKey(name);
 // if (settings is DynamicJsonObject)
 // try
 // {
 // return settings[name] != null;
 // }
 // catch (KeyNotFoundException)
 // {
 // return false;
 // }
 // return settings.GetType().GetProperty(name) != null;
 // }

 public static bool IsPropertyExistBinderException(dynamic dynamicObj, string property)
 {
 try
 {
 var value = dynamicObj[property].Value;
 return true;
 }
 catch (RuntimeBinderException)
 {

 return false;
 }

 }

 public static bool HasPropertyFoundException(dynamic obj, string name)
 {
 try
 {
 var value = obj[name];
 return true;
 }
 catch (KeyNotFoundException)
 {
 return false;
 }
 }


 public static bool doesPropertyExist(dynamic obj, string property)
 {
 return ((Type)obj.GetType()).GetProperties().Where(p =&gt; p.Name.Equals(property)).Any();
 }

 public static bool PropertyExistsJToken(dynamic obj, string name)
 {
 if (obj == null) return false;
 if (obj is ExpandoObject)
 return ((IDictionary&lt;string, object&gt;)obj).ContainsKey(name);
 if (obj is IDictionary&lt;string, object&gt; dict1)
 return dict1.ContainsKey(name);
 if (obj is IDictionary&lt;string, JToken&gt; dict2)
 return dict2.ContainsKey(name);
 return obj.GetType().GetProperty(name) != null;
 }

 // public static bool PropertyExistsJsonObject(dynamic settings, string name)
 // {
 // if (settings is ExpandoObject)
 // return ((IDictionary&lt;string, object&gt;)settings).ContainsKey(name);
 // else if (settings is DynamicJsonObject)
 // return ((DynamicJsonObject)settings).GetDynamicMemberNames().Contains(name);

 // return settings.GetType().GetProperty(name) != null;
 // }
}
</code></pre>
doesPropertyExist
Time:59.5907507s Memory:403680
HasProperty
Time:30.8231781s Memory:14968
IsPropertyExist
Time:39.6179575s Memory:97000
IsPropertyExistBinderException throw find
PropertyExists
Time:56.009761s Memory:13464
PropertyExistsJToken
Time:61.6146953s Memory:15952

blocks|key|607668|text|为了节省其他人的时间，这个答案覆盖了很多人，他们使用Newtonstoft+Json动态反序列化来搜索这个问题：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|607669|dynamic+dynamicObject+=+JsonConvert.DeserializeObject<dynamic>(json);
if+(IsContainsKey(dynamicObject,+"searchText"))
++++searchText+=+dynamicObject.searchText;

bool+IsContainsKey(dynamic+newtonsoftDynamic,+string+propertyName)+{
++++return+(newtonsoftDynamic+as+JObject).ContainsKey(propertyName);
}|code-block|syntax|javascript|607670|或者只是在代码中：|607671|JObject+obj+=+dynamicObject+as+JObject;
string+searchText+=+string.Empty;
if+(obj.ContainsKey("searchText"))
++++searchText+=+obj.Value<string>("searchText");|607672|没有异常，通过Newtonsoft正确处理，但您仍然可以使用dynamicObject.xxx的属性，您知道将始终在那里。|607673|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

To save others some time and this answer covers a lot of the people Googling this question using Newtonstoft Json deserialization with dynamics:
<pre><code>dynamic dynamicObject = JsonConvert.DeserializeObject&lt;dynamic&gt;(json);
if (IsContainsKey(dynamicObject, &quot;searchText&quot;))
 searchText = dynamicObject.searchText;

bool IsContainsKey(dynamic newtonsoftDynamic, string propertyName) {
 return (newtonsoftDynamic as JObject).ContainsKey(propertyName);
}
</code></pre>
or just in code:
<pre><code>JObject obj = dynamicObject as JObject;
string searchText = string.Empty;
if (obj.ContainsKey(&quot;searchText&quot;))
 searchText = obj.Value&lt;string&gt;(&quot;searchText&quot;);
</code></pre>
no exceptions, proper handling via Newtonsoft but you can still use the dynamicObject.xxx for properties you know will always be there.

I have an anonymous type object that I receive as a dynamic from a method
I would like to check in a property exists on that object.

<pre><code>....
var settings = new {
 Filename="temp.txt",
 Size=10
}
...

function void Settings(dynamic settings) {
var exists = IsSettingExist(settings,"Filename")
}
</code></pre>

How would I implement IsSettingExist ?

How do I check if a property exists on a dynamic anonymous type in c#?

我有一个匿名类型对象，它是我从一个方法接收的动态对象，我想检查该对象上是否存在一个属性。....var settings = new {                   Filename="temp.txt",                   Size=10}...function void Settings(dynamic settings) {var exists = IsSettin

问如何在c#中检查动态匿名类型上是否存在属性？
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