blocks|key|1214403|text|baseKey+choice;
if+(Enum.TryParse("HKEY_LOCAL_MACHINE",+out+choice))+{
+++++uint+value+=+(uint)choice;

+++++//+`value`+is+what+you're+looking+for

}+else+{+/*+error:+the+string+was+not+an+enum+member+*/+}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1214404|在.NET+4.5之前，您必须执行以下操作，这更容易出错，并且在传递无效字符串时会抛出异常：|unstyled|1214405|(uint)Enum.Parse(typeof(baseKey),+"HKEY_LOCAL_MACHINE")|1214406|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>baseKey choice;
if (Enum.TryParse("HKEY_LOCAL_MACHINE", out choice)) {
 uint value = (uint)choice;

 // `value` is what you're looking for

} else { /* error: the string was not an enum member */ }
</code></pre>

Before .NET 4.5, you had to do the following, which is more error-prone and throws an exception when an invalid string is passed:

<pre><code>(uint)Enum.Parse(typeof(baseKey), "HKEY_LOCAL_MACHINE")
</code></pre>

blocks|key|1429260|text|var+value+=+(uint)+Enum.Parse(typeof(baseKey),+"HKEY_LOCAL_MACHINE");++|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1429261|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>var value = (uint) Enum.Parse(typeof(baseKey), "HKEY_LOCAL_MACHINE"); 
</code></pre>

blocks|key|1429283|text|通过一些错误处理...|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1429284|uint+key+=+0;
string+s+=+"HKEY_LOCAL_MACHINE";
try
{
+++key+=+(uint)Enum.Parse(typeof(baseKey),+s);
}
catch(ArgumentException)
{
+++//unknown+string+or+s+is+null
}|code-block|syntax|javascript|1429285|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|$]]

With some error handling...

<pre><code>uint key = 0;
string s = "HKEY_LOCAL_MACHINE";
try
{
 key = (uint)Enum.Parse(typeof(baseKey), s);
}
catch(ArgumentException)
{
 //unknown string or s is null
}
</code></pre>

blocks|key|1214503|text|使用Enum.TryParse，你不需要异常处理：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1214504|baseKey+e;

if+(+Enum.TryParse(s,+out+e)+)
{
+...
}|code-block|syntax|javascript|1214505|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|$]]

Using Enum.TryParse you don't need the Exception handling:

<pre><code>baseKey e;

if ( Enum.TryParse(s, out e) )
{
 ...
}
</code></pre>

blocks|key|1429433|text|替代解决方案可以是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1429434|baseKey+hKeyLocalMachine+=+baseKey.HKEY_LOCAL_MACHINE;
uint+value+=+(uint)hKeyLocalMachine;|code-block|syntax|javascript|1429435|或者只是：|1429436|uint+value+=+(uint)baseKey.HKEY_LOCAL_MACHINE;|1429437|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|$]]

Alternate solution can be:

<pre><code>baseKey hKeyLocalMachine = baseKey.HKEY_LOCAL_MACHINE;
uint value = (uint)hKeyLocalMachine;
</code></pre>

Or just:

<pre><code>uint value = (uint)baseKey.HKEY_LOCAL_MACHINE;
</code></pre>

blocks|key|1429510|text|var+value+=+(uint)Enum.Parse(typeof(basekey),+"HKEY_LOCAL_MACHINE",+true);|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1429511|这段代码演示了如何从字符串中获取枚举值。要从字符串转换，需要使用静态Enum.Parse()方法，该方法有3个参数。第一个是您要考虑的枚举类型。语法是关键字typeof()，后跟括号中的枚举类的名称。第二个参数是要转换的字符串，第三个参数是一个bool，指示在执行转换时是否应该忽略大小写。|unstyled|offset|length|style|CODE|1429512|最后，请注意Enum.Parse()实际上返回了一个对象引用，这意味着您需要显式地将其转换为所需的枚举类型(string、int等)。|1429513|谢谢。|1429514|entityMap^0|0|Y|C|26|8|3E|4|0|6|C|1I|6|1P|3|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|R|8|@$G|S|H|T|I|J]|$G|U|H|V|I|J]|$G|W|H|X|I|J]]|9|@]|A|$]]|$1|K|3|L|5|F|7|Y|8|@$G|Z|H|10|I|J]|$G|11|H|12|I|J]|$G|13|H|14|I|J]]|9|@]|A|$]]|$1|M|3|N|5|F|7|15|8|@]|9|@]|A|$]]|$1|O|3|-4|5|F|7|16|8|@]|9|@]|A|$]]]|P|$]]

<pre><code>var value = (uint)Enum.Parse(typeof(basekey), "HKEY_LOCAL_MACHINE", true);
</code></pre>

This code snippet illustrates obtaining an enum value from a string. To convert from a string, you need to use the static <code>Enum.Parse()</code> method, which takes 3 parameters. The first is the type of enum you want to consider. The syntax is the keyword <code>typeof()</code> followed by the name of the enum class in brackets. The second parameter is the string to be converted, and the third parameter is a <code>bool</code> indicating whether you should ignore case while doing the conversion. 

Finally, note that <code>Enum.Parse()</code> actually returns an object reference, that means you need to explicitly convert this to the required enum type(<code>string</code>,<code>int</code> etc).

Thank you.

I have an enum:

<pre><code>public enum baseKey : uint
{ 
 HKEY_CLASSES_ROOT = 0x80000000,
 HKEY_CURRENT_USER = 0x80000001,
 HKEY_LOCAL_MACHINE = 0x80000002,
 HKEY_USERS = 0x80000003,
 HKEY_CURRENT_CONFIG = 0x80000005
}
</code></pre>

How can I, given the string <code>HKEY_LOCAL_MACHINE</code>, get a value <code>0x80000002</code> based on the enum?

How to get a enum value from string in C#?

我有一个枚举：public enum baseKey : uint{      HKEY_CLASSES_ROOT = 0x80000000,    HKEY_CURRENT_USER = 0x80000001,    HKEY_LOCAL_MACHINE = 0x80000002,    HKEY_USERS = 0...

问如何在C#中从字符串中获取枚举值？
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