C# determines the object type based on string representation

In C#, a string containing the type name can be converted to the corresponding Type object. However, the method used for this conversion depends on whether the type is defined in the same assembly as the calling code, or in a different assembly.

Use Type.GetType(string)

If the type is defined in the same assembly, you can use the Type.GetType(string) method and provide a fully qualified type name as a string. For example, to get the Type of the int data type, you can use:

Type.GetType("System.Int32");

Use Assembly.GetType(string)

If the type is defined in a different assembly, you also need to provide the assembly name. It can be implemented using the Assembly.GetType(string) method. First, get a reference to the assembly, and then use that reference to get Type:

Assembly asm = typeof(SomeKnownType).Assembly;
Type type = asm.GetType("Namespace.MyClass");

Namespace and assembly qualifications

Ensure that the namespace of type is included in the string provided to Type.GetType() or Assembly.GetType(). Additionally, for strongly named assemblies, it may be necessary to include full assembly identity, including version, culture, and public key tags.

Sample Scene

Consider the following scenario where a string contains a fully qualified name of the type:

string typeName = "Namespace.MyClass, MyAssembly";

Depending on whether MyAssembly is referenced by the called assembly, you can use Type.GetType() or Assembly.GetType():

// 如果 MyAssembly 被引用
Type type1 = Type.GetType(typeName);

// 如果 MyAssembly 未被引用
Assembly asm = typeof(SomeKnownType).Assembly;
Type type2 = asm.GetType(typeName);