blocks|key|1424379|text|您可以这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1424380|typeof(MyObject).GetProperty("MyProperty")|code-block|syntax|javascript|1424381|但是，由于C#没有"symbol“类型，因此没有什么可以帮助您避免使用字符串。顺便说一句，为什么你称这种类型是不安全的？|1424382|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

You can do this:

<pre><code>typeof(MyObject).GetProperty("MyProperty")
</code></pre>

However, since C# doesn't have a "symbol" type, there's nothing that will help you avoid using string. Why do you call this type-unsafe, by the way?

blocks|key|1424517|text|反射用于运行时类型计算。因此，您的字符串常量不能在编译时验证。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1424518|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Reflection is used for runtime type evaluation. So your string constants cannot be verified at compile time.

blocks|key|1424560|text|有一种不使用字符串的lambdas/Expression的.NET+3.5方式...|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1424561|using+System;
using+System.Linq.Expressions;
using+System.Reflection;

class+Foo
{
++++public+string+Bar+{+get;+set;+}
}
static+class+Program
{
++++static+void+Main()
++++{
++++++++PropertyInfo+prop+=+PropertyHelper<Foo>.GetProperty(x+=>+x.Bar);
++++}
}
public+static+class+PropertyHelper<T>
{
++++public+static+PropertyInfo+GetProperty<TValue>(
++++++++Expression<Func<T,+TValue>>+selector)
++++{
++++++++Expression+body+=+selector;
++++++++if+(body+is+LambdaExpression)
++++++++{
++++++++++++body+=+((LambdaExpression)body).Body;
++++++++}
++++++++switch+(body.NodeType)
++++++++{
++++++++++++case+ExpressionType.MemberAccess:
++++++++++++++++return+(PropertyInfo)((MemberExpression)body).Member;
++++++++++++default:
++++++++++++++++throw+new+InvalidOperationException();
++++++++}
++++}
}|code-block|syntax|javascript|1424562|entityMap^0|I|A|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

There is a .NET 3.5 way with lambdas/<code>Expression</code> that doesn't use strings...

<pre><code>using System;
using System.Linq.Expressions;
using System.Reflection;

class Foo
{
 public string Bar { get; set; }
}
static class Program
{
 static void Main()
 {
 PropertyInfo prop = PropertyHelper&lt;Foo&gt;.GetProperty(x =&gt; x.Bar);
 }
}
public static class PropertyHelper&lt;T&gt;
{
 public static PropertyInfo GetProperty&lt;TValue&gt;(
 Expression&lt;Func&lt;T, TValue&gt;&gt; selector)
 {
 Expression body = selector;
 if (body is LambdaExpression)
 {
 body = ((LambdaExpression)body).Body;
 }
 switch (body.NodeType)
 {
 case ExpressionType.MemberAccess:
 return (PropertyInfo)((MemberExpression)body).Member;
 default:
 throw new InvalidOperationException();
 }
 }
}
</code></pre>

blocks|key|1424650|text|你可以使用新的nameof()运算符，它是C#+6的一部分，在Visual+Studio2015中可用。更多信息here。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1424651|在您的示例中，您将使用：|1424652|PropertyInfo+result+=+typeof(MyObject).GetProperty(nameof(MyObject.MyProperty));|code-block|syntax|javascript|1424653|编译器会将nameof(MyObject.MyProperty)转换为字符串"MyProperty“，但您可以获得重构属性名而不必记住更改字符串的好处，因为Visual+Studio、ReSharper等知道如何重构nameof()值。|1424654|entityMap|0|LINK|mutability|MUTABLE|url|https://msdn.microsoft.com/en-us/library/dn986596.aspx^0|7|8|1K|4|0|0|0|0|5|R|30|8|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@$9|Z|A|10|1|11]]|E|$]]|$1|F|3|G|5|6|7|12|8|@]|D|@]|E|$]]|$1|H|3|I|5|J|7|13|8|@]|D|@]|E|$K|L]]|$1|M|3|N|5|6|7|14|8|@$9|15|A|16|B|C]|$9|17|A|18|B|C]]|D|@]|E|$]]|$1|O|3|-4|5|6|7|19|8|@]|D|@]|E|$]]]|P|$Q|$5|R|S|T|E|$U|V]]]]

You can use the new <code>nameof()</code> operator that is part of C# 6 and available in Visual Studio 2015. More info <a href="https://msdn.microsoft.com/en-us/library/dn986596.aspx" rel="noreferrer">here</a>.

For your example you would use:

<pre><code>PropertyInfo result = typeof(MyObject).GetProperty(nameof(MyObject.MyProperty));
</code></pre>

The compiler will convert <code>nameof(MyObject.MyProperty)</code> to the string "MyProperty" but you gain the benefit of being able to refactor the property name without having to remember to change the string because Visual Studio, ReSharper, and the like know how to refactor <code>nameof()</code> values.

I want to get the PropertyInfo for a specific property. I could use:

<pre><code>foreach(PropertyInfo p in typeof(MyObject).GetProperties())
{
 if ( p.Name == "MyProperty") { return p }
}
</code></pre>

But there must be a way to do something similar to 

<pre><code>typeof(MyProperty) as PropertyInfo
</code></pre>

Is there? Or am I stuck doing a type-unsafe string comparison?

Cheers.

How to get the PropertyInfo of a specific property?

Visual Studio

编译器

我想要获取特定属性的PropertyInfo。我可以使用：foreach(PropertyInfo p in typeof(MyObject).GetProperties()){    if ( p.Name == "MyProperty") { return p }}但必须有一种方法来做一些类似的事情typeof(M...

问如何获取特定属性的PropertyInfo？
EN

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问如何获取特定属性的PropertyInfo？EN

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问如何获取特定属性的PropertyInfo？
EN