How Can I Cast an Anonymous Type in C# to Access Its Properties?

Cast Anonymous Type to Access Properties

Casting an anonymous type back to its original type can be problematic when accessing its properties. To solve this, one can utilize a trick to infer the correct type.

Tricking the Compiler

The method Cast accepts an object x and a type holder typeHolder of the desired type. By passing the anonymous type a as typeHolder, the compiler can infer the type to cast x to:

private static T Cast<T>(T typeHolder, Object x)
{
    // typeHolder above is just for compiler magic
    // to infer the type to cast x to
    return (T)x;
}

Usage:

var a = new { Id = 1, Name = "Bob" };
TestMethod(a);
...
private static void TestMethod(Object x)
{
    // This is a dummy value, just to get 'a' to be of the right type
    var a = new { Id = 0, Name = "" };
    a = Cast(a, x);
    Console.Out.WriteLine(a.Id + ": " + a.Name);
}

Alternative Casting Method

An alternative method is to create an extension method CastTo, which takes the value to be cast and the target type:

private static T CastTo<T>(this Object value, T targetType)
{
    // targetType above is just for compiler magic
    // to infer the type to cast value to
    return (T)value;
}

Usage:

var value = x.CastTo(a);

Recommendation

While these techniques allow for casting anonymous types, it is recommended to use real types for clarity and ease of use.

The above is the detailed content of How Can I Cast an Anonymous Type in C# to Access Its Properties?. For more information, please follow other related articles on the PHP Chinese website!