How do i assigned the type of any object to a .NET generic method?
Suppose that I have created a method like this
private void Test<t>(t str)
{
}
Now 开发者_开发百科from another method i call it
private void BtnClick()
{
string a = "";
test<Here I Want To assign The Type what ever the type of 'a' is>();
}
How can I do this ?
Well, if a
is a string, you can write:
Test<string>(a);
And if a
is an int
, you can write:
Test<int>(a);
Pretty obvious. If you don't know the type of a
upfront, that means that BtnClick
should be generic, the problem would be moved to BtnClick
's caller:
private void BtnClick<T>()
{
T a = ...;
Test<T>(a);
}
C# 2.0 and later offers type inference, so you wouldn't have to specify the type:
Test(a);
You simply call the function passing a
as the parameter. Type inference will determine what T should be for a
.
static void Main()
{
string temp = "blah";
Test(temp);
Console.Read();
}
private static void Test<T>(T input)
{
Console.WriteLine(typeof(T).ToString());
}
System.String
would be printed to the console.
Edit: But, yes, absent type inference, and when you know what your type your variable is, you can always be explicit with the type. Test<string>(temp);
In your example, a
is always a string
, so you can simply use either Test<string>(a)
or Test(a)
. If, however, you mean that you have a Type
instance hanging around somewhere, then you get into the area of reflection. Note that this works, but is slow if used in a tight-loop, so make sure that you understand the performance aspect;
object arg = ...;
MethodInfo method = typeof(YourType)
.GetMethod("Test", BindingFlags.NonPublic | BindingFlags.Instance)
.MakeGenericMethod(arg.GetType());
method.Invoke(this, new object[] { arg });
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