C# 中的可空方法参数
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Nullable Method Arguments in C#
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Duplicate Question
重复问题
Passing null arguments to C# methods
Can I do this in c# for .Net 2.0?
我可以在 c# 中为 .Net 2.0 执行此操作吗？
public void myMethod(string astring, int? anint)
{
//some code in which I may have an int to work with
//or I may not...
}
If not, is there something similar I can do?
如果没有，我可以做类似的事情吗？
采纳答案by roryf
Yes, assuming you added the chevrons deliberately and you really meant:
是的，假设您故意添加了 V 形，并且您的意思是：
public void myMethod(string astring, int? anint)
anintwill now have a HasValueproperty.
anint现在将拥有一个HasValue属性。
回答by Dead account
In C# 2.0 you can do;
在 C# 2.0 中你可以这样做；
public void myMethod(string astring, int? anint)
{
//some code in which I may have an int to work with
//or I may not...
}
And call the method like
并调用方法
myMethod("Hello", 3);
myMethod("Hello", null);
回答by Inferis
Depends on what you want to achieve. If you want to be able to drop the anintparameter, you have to create an overload:
取决于你想要达到的目标。如果您希望能够删除anint参数，则必须创建一个重载：
public void myMethod(string astring, int anint)
{
}
public void myMethod(string astring)
{
myMethod(astring, 0); // or some other default value for anint
}
You can now do:
你现在可以这样做：
myMethod("boo"); // equivalent to myMethod("boo", 0);
myMethod("boo", 12);
If you want to pass a nullable int, well, see the other answers. ;)
如果你想传递一个可为空的 int，那么，请参阅其他答案。;)
