blocks|key|1003900|text|您使用了collection+initializer语法，但是您仍然需要首先创建一个new+Dictionary<string,+string>对象，因为快捷语法会被转换为一堆Add()调用(就像您的代码一样)：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1003901|var+data+=+new+Dictionary<string,+string>
{
++++{+"test",+"val"+},+
++++{+"test2",+"val2"+}
};|code-block|syntax|javascript|1003902|在C#+6中，您现在可以选择对字典以及任何其他支持indexers的类型使用更直观的语法。上面的语句可以重写为：|1003903|var+data+=+new+Dictionary<string,+string>
{
++++["test"]+=+"val",
++++["test2"]+=+"val2"
};|1003904|与集合初始化器不同，它在幕后调用索引器设置器，而不是适当的Add()方法。|1003905|entityMap|0|LINK|mutability|MUTABLE|url|https://msdn.microsoft.com/en-us/library/bb384062.aspx|1|https://msdn.microsoft.com/en-us/library/6x16t2tx.aspx^0|16|U|2G|5|4|M|0|0|0|P|8|1|0|0|T|5|0^^$0|@$1|2|3|4|5|6|7|10|8|@$9|11|A|12|B|C]|$9|13|A|14|B|C]]|D|@$9|15|A|16|1|17]]|E|$]]|$1|F|3|G|5|H|7|18|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|19|8|@]|D|@$9|1A|A|1B|1|1C]]|E|$]]|$1|M|3|N|5|H|7|1D|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|1E|8|@$9|1F|A|1G|B|C]]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|1H|8|@]|D|@]|E|$]]]|R|$S|$5|T|U|V|E|$W|X]]|Y|$5|T|U|V|E|$W|Z]]]]

You use the <a href="https://msdn.microsoft.com/en-us/library/bb384062.aspx" rel="noreferrer">collection initializer</a> syntax, but you still need to make a <code>new Dictionary&lt;string, string&gt;</code> object first as the shortcut syntax is translated to a bunch of <code>Add()</code> calls (like your code):

<pre><code>var data = new Dictionary&lt;string, string&gt;
{
 { "test", "val" }, 
 { "test2", "val2" }
};
</code></pre>

In C# 6, you now have the option of using a more intuitive syntax with Dictionary as well as any other type that supports <a href="https://msdn.microsoft.com/en-us/library/6x16t2tx.aspx" rel="noreferrer">indexers</a>. The above statement can be rewritten as:

<pre><code>var data = new Dictionary&lt;string, string&gt;
{
 ["test"] = "val",
 ["test2"] = "val2"
};
</code></pre>

Unlike collection initializers, this invokes the indexer setter under the hood, rather than an appropriate <code>Add()</code> method.

blocks|key|1003974|text|虽然，字典初始化器的答案是完全正确的，但我想指出另一种方法(但我可能不推荐这样做)。如果你的目标是提供简洁的API用法，你可以使用匿名对象。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1003975|var+data+=+new+{+test1+=+"val",+test2+=+"val2"};|code-block|syntax|javascript|1003976|因此，"data“变量是一个”无法描述“的匿名类型，因此只能将其作为System.Object传递。然后，您可以编写代码，将匿名对象转换为字典。这样的代码将依赖于反射，这可能会很慢。但是，您可以使用System.Reflection.Emit或System.Linq.Expressions来编译和缓存委托，这将使后续调用速度更快。|offset|length|style|CODE|1003977|在我见过的许多地方，Asp.net+MVC都使用了这种技术。许多Html+Helper都有接受对象或字典的重载。我假设他们的API设计的目标和你所追求的是一样的；在方法调用中使用简洁的语法。|1003978|entityMap^0|0|0|Y|D|2R|M|3E|N|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@$I|T|J|U|K|L]|$I|V|J|W|K|L]|$I|X|J|Y|K|L]]|9|@]|A|$]]|$1|M|3|N|5|6|7|Z|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|10|8|@]|9|@]|A|$]]]|P|$]]

While, the dictionary initializer answer is totally correct, there is another approach to this that I would point out (but I might not recommend it). If your goal is to provide terse API usage, you could use anonymous objects.

<pre><code>var data = new { test1 = "val", test2 = "val2"};
</code></pre>

The "data" variable is then of an "unspeakable" anonymous type, so you could only pass this around as <code>System.Object</code>. You could then write code that can transform an anonymous object into a dictionary. Such code would rely on reflection, which would potentially be slow. However, you could use <code>System.Reflection.Emit</code>, or <code>System.Linq.Expressions</code> to compile and cache a delegate that would make subsequent calls much faster.

Asp.net MVC APIs use this technique in a number of places that I've seen. A lot of the Html Helpers have overloads that accept either an object or a dictionary. I assume the goal of their API design is the same as what you are after; terse syntax at the method call.

blocks|key|790057|text|使用DynamicObject，创建一个更简单的字典初始化器并不困难。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|790058|假设您想要调用以下方法|790059|void+PrintDict(IDictionary<string,+object>+dict)+{
++++foreach(var+kv+in+dict)+{
++++++++Console.WriteLine+("++->+"+%2B+kv.Key+%2B+"+=+"+%2B+kv.Value);
++++}
}|code-block|syntax|javascript|790060|使用文字语法，如|790061|var+dict+=+Dict+(Hello:+"World",+IAm:+"a+dictionary");
PrintDict+(dict);|790062|这可以通过创建动态对象来实现，如下所示|790063|dynamic+Dict+{
++++get+{
++++++++return+new+DynamicDictFactory+();
++++}
}

private+class+DynamicDictFactory+:+DynamicObject
{
++++public+override+bool+TryInvoke+(InvokeBinder+binder,+object[]+args,+out+object+result)
++++{
++++++++var+res+=+new+Dictionary<string,+object>+();
++++++++var+names+=+binder.CallInfo.ArgumentNames;

++++++++for+(var+i+=+0;+i+<+args.Length;+i%2B%2B)+{
++++++++++++var+argName+=+names+[i];
++++++++++++if(string.IsNullOrEmpty(argName))+throw+new+ArgumentException();
++++++++++++res+[argName]+=+args+[i];
++++++++}
++++++++result+=+res;
++++++++return+true;
++++}
}|790064|entityMap^0|2|D|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Z|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|10|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|11|8|@]|D|@]|E|$]]|$1|O|3|P|5|J|7|12|8|@]|D|@]|E|$K|L]]|$1|Q|3|R|5|6|7|13|8|@]|D|@]|E|$]]|$1|S|3|T|5|J|7|14|8|@]|D|@]|E|$K|L]]|$1|U|3|-4|5|6|7|15|8|@]|D|@]|E|$]]]|V|$]]

Using <code>DynamicObject</code>, it is not that difficult to create a simpler dictionary initializer.

Imagine you want to call the following method

<pre><code>void PrintDict(IDictionary&lt;string, object&gt; dict) {
 foreach(var kv in dict) {
 Console.WriteLine (" -&gt; " + kv.Key + " = " + kv.Value);
 }
}
</code></pre>

using a literal syntax like

<pre><code>var dict = Dict (Hello: "World", IAm: "a dictionary");
PrintDict (dict);
</code></pre>

This can be accomplished by creating a dynamic object like this

<pre><code>dynamic Dict {
 get {
 return new DynamicDictFactory ();
 }
}

private class DynamicDictFactory : DynamicObject
{
 public override bool TryInvoke (InvokeBinder binder, object[] args, out object result)
 {
 var res = new Dictionary&lt;string, object&gt; ();
 var names = binder.CallInfo.ArgumentNames;

 for (var i = 0; i &lt; args.Length; i++) {
 var argName = names [i];
 if(string.IsNullOrEmpty(argName)) throw new ArgumentException();
 res [argName] = args [i];
 }
 result = res;
 return true;
 }
}
</code></pre>

I currently have a WebSocket between JavaScript and a server programmed in C#. In JavaScript, I can pass data easily using an associative array:

<pre><code>var data = {'test': 'val',
 'test2': 'val2'};
</code></pre>

To represent this data object on the server side, I use a <code>Dictionary&lt;string, string&gt;</code>, but this is more 'typing-expensive' than in JavaScript:

<pre><code>Dictionary&lt;string, string&gt; data = new Dictionary&lt;string,string&gt;();
data.Add("test", "val");
data.Add("test2", "val2");
</code></pre>

Is there some kind of literal notation for associative arrays / <code>Dictionary</code>s in C#?

Literal notation for Dictionary in C#?

服务器

我目前在JavaScript和用C#编程的服务器之间有一个WebSocket。在JavaScript中，我可以使用关联数组轻松地传递数据：var data = {'test': 'val', 'test2': 'val2'};为了在服务器端表示这个数据对象，我使用了一个Dictionary<str...

问C#中的字典的文字表示法？
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