Gets the Type with the specified name, performing a case-sensitive search and specifying whether to throw an exception if the type is not found.
public:
static Type ^ GetType(System::String ^ typeName, bool throwOnError);
public static Type GetType(string typeName, bool throwOnError);
public static Type? GetType(string typeName, bool throwOnError);
static member GetType : string * bool -> Type
Public Shared Function GetType (typeName As String, throwOnError As Boolean) As Type
Parameters
The assembly-qualified name of the type to get. See AssemblyQualifiedName. If the type is in the currently executing assembly or in mscorlib.dll/System.Private.CoreLib.dll, it's sufficient to supply the type name qualified by its namespace.
true
to throw an exception if the type cannot be found; false
to return null
. Specifying false
also suppresses some other exception conditions, but not all of them. See the Exceptions section.
The type with the specified name. If the type is not found, the throwOnError
parameter specifies whether null
is returned or an exception is thrown. In some cases, an exception is thrown regardless of the value of throwOnError
. See the Exceptions section.
A class initializer is invoked and throws an exception.
throwOnError
is true
and the type is not found.
-or-
throwOnError
is true
and typeName
contains invalid characters, such as an embedded tab.
-or-
throwOnError
is true
and typeName
is an empty string.
-or-
throwOnError
is true
and typeName
represents an array type with an invalid size.
-or-
typeName
represents an array of TypedReference.
throwOnError
is true
and typeName
contains invalid syntax. For example, "MyType[,*,]".
-or-
typeName
represents a generic type that has a pointer type, a ByRef
type, or Void as one of its type arguments.
-or-
typeName
represents a generic type that has an incorrect number of type arguments.
-or-
typeName
represents a generic type, and one of its type arguments does not satisfy the constraints for the corresponding type parameter.
throwOnError
is true
and the assembly or one of its dependencies was not found.
The assembly or one of its dependencies is not valid for the currently loaded runtime.
ExamplesThe following example retrieves the type of System.Int32
and uses that type object to display the FullName property of System.Int32
. If a type object refers to an assembly that does not exist, this example throws an exception.
using System;
class Example
{
public static void Main()
{
try {
// Get the type of a specified class.
Type myType1 = Type.GetType("System.Int32");
Console.WriteLine("The full name is {0}.\n", myType1.FullName);
}
catch (TypeLoadException e)
{
Console.WriteLine("{0}: Unable to load type System.Int32", e.GetType().Name);
}
try {
// Since NoneSuch does not exist in this assembly, GetType throws a TypeLoadException.
Type myType2 = Type.GetType("NoneSuch", true);
Console.WriteLine("The full name is {0}.", myType2.FullName);
}
catch(TypeLoadException e) {
Console.WriteLine("{0}: Unable to load type NoneSuch", e.GetType().Name);
}
}
}
// The example displays the following output:
// The full name is System.Int32.
//
// TypeLoadException: Unable to load type NoneSuch
open System
try
// Get the type of a specified class.
let myType1 = Type.GetType "System.Int32"
printfn $"The full name is {myType1.FullName}.\n"
with :? TypeLoadException as e ->
printfn $"{e.GetType().Name}: Unable to load type System.Int32"
try
// Since NoneSuch does not exist in this assembly, GetType throws a TypeLoadException.
let myType2 = Type.GetType("NoneSuch", true)
printfn $"The full name is {myType2.FullName}."
with :? TypeLoadException as e ->
printfn $"{e.GetType().Name}: Unable to load type NoneSuch"
// The example displays the following output:
// The full name is System.Int32.
//
// TypeLoadException: Unable to load type NoneSuch
Class Example
Public Shared Sub Main()
Try
' Get the type of the specified class.
Dim myType1 As Type = Type.GetType("System.Int32")
Console.WriteLine("The full name is {0}.", myType1.FullName)
Catch e As TypeLoadException
Console.WriteLine("{0}: Unable to load type System.Int32",
e.GetType().Name)
End Try
Console.WriteLine()
Try
' Since NoneSuch does not exist in this assembly, GetType throws a TypeLoadException.
Dim myType2 As Type = Type.GetType("NoneSuch", True)
Console.WriteLine("The full name is {0}.", myType2.FullName)
Catch e As TypeLoadException
Console.WriteLine("{0}: Unable to load type NoneSuch", e.GetType().Name)
End Try
End Sub
End Class
' The example displays the following output:
' The full name is System.Int32.
'
' TypeLoadException: Unable to load type NoneSuch
Remarks
You can use the GetType method to obtain a Type object for a type in another assembly if you know its assembly-qualified name, which can be obtained from AssemblyQualifiedName. GetType causes loading of the assembly specified in typeName
. You can also load an assembly using the Assembly.Load method, and then use the Assembly.GetType or Assembly.GetTypes method to get Type objects. If a type is in an assembly known to your program at compile time, it's more efficient to use typeof
in C# or the GetType
operator in Visual Basic.
.NET Framework only: GetType only works on assemblies loaded from disk. If you call GetType to look up a type defined in a dynamic assembly defined using the System.Reflection.Emit services, you might get inconsistent behavior. The behavior depends on whether the dynamic assembly is persistent, that is, created using the RunAndSave
or Save
access modes of the System.Reflection.Emit.AssemblyBuilderAccess enumeration. If the dynamic assembly is persistent and has been written to disk before GetType
is called, the loader finds the saved assembly on disk, loads that assembly, and retrieves the type from that assembly. If the assembly has not been saved to disk when GetType
is called, the method returns null
. GetType
does not understand transient dynamic assemblies; therefore, calling GetType
to retrieve a type in a transient dynamic assembly returns null
.
In .NET Framework, to use GetType
on a dynamic module, subscribe to the AppDomain.AssemblyResolve event and call GetType
before saving. Otherwise, you will get two copies of the assembly in memory.
On .NET Core 3.0 and later versions, assembly loads triggered by this API are affected by the current value of AssemblyLoadContext.CurrentContextualReflectionContext.
The throwOnError
parameter specifies what happens when the type is not found, and also suppresses certain other exception conditions, as described in the Exceptions section. Some exceptions are thrown regardless of the value of throwOnError
. For example, if the type is found but cannot be loaded, a TypeLoadException is thrown even if throwOnError
is false
.
The following table shows what members of a base class are returned by the Get
methods when reflecting on a type.
Hide-by-name-and-signature considers all of the parts of the signature, including custom modifiers, return types, parameter types, sentinels, and unmanaged calling conventions. This is a binary comparison.
For reflection, properties and events are hide-by-name-and-signature. If you have a property with both a get and a set accessor in the base class, but the derived class has only a get accessor, the derived class property hides the base class property, and you will not be able to access the setter on the base class.
Custom attributes are not part of the common type system.
Arrays or COM types are not searched for unless they have already been loaded into the table of available classes.
typeName
can be the type name qualified by its namespace or an assembly-qualified name that includes an assembly name specification. See AssemblyQualifiedName.
If typeName
includes the namespace but not the assembly name, this method searches only the calling object's assembly and mscorlib.dll/System.Private.CoreLib.dll, in that order. If typeName is fully qualified with the partial or complete assembly name, this method searches in the specified assembly. If the assembly has a strong name, a complete assembly name is required.
The AssemblyQualifiedName property returns a fully qualified type name including nested types, the assembly name, and generic arguments. All compilers that support the common language runtime will emit the simple name of a nested class, and reflection constructs a mangled name when queried, in accordance with the following conventions.
Note
Processor architecture is part of assembly identity, and can be specified as part of assembly name strings. For example, "ProcessorArchitecture=msil". However, it's not included in the string returned by the AssemblyQualifiedName property, for compatibility reasons. You can also load types by creating an AssemblyName object and passing it to an appropriate overload of the Load method. You can then use the Assembly.GetType method to load types from the assembly. See also AssemblyName.ProcessorArchitecture.
Delimiter Meaning Backslash (\) Escape character. Backtick (`) Precedes one or more digits representing the number of type parameters, located at the end of the name of a generic type. Brackets ([]) Enclose a generic type argument list, for a constructed generic type; within a type argument list, enclose an assembly-qualified type. Comma (,) Precedes the Assembly name. Period (.) Denotes namespace identifiers. Plus sign (+) Precedes a nested class.For example, the fully qualified name for a class might look like this:
TopNamespace.SubNameSpace.ContainingClass+NestedClass,MyAssembly
If the namespace were TopNamespace.Sub+Namespace, then the string would have to precede the plus sign (+) with an escape character (\) to prevent it from being interpreted as a nesting separator. Reflection emits this string as follows:
TopNamespace.Sub\+Namespace.ContainingClass+NestedClass,MyAssembly
A "++" becomes "\+\+", and a "\" becomes "\\".
This qualified name can be persisted and later used to load the Type. To search for and load a Type, use GetType either with the type name only or with the assembly qualified type name. GetType with the type name only will look for the Type in the caller's assembly and then in the System assembly. GetType with the assembly qualified type name will look for the Type in any assembly.
Type names may include trailing characters that denote additional information about the type, such as whether the type is a reference type, a pointer type or an array type. To retrieve the type name without these trailing characters, use t.GetElementType().ToString()
, where t
is the type.
Spaces are relevant in all type name components except the assembly name. In the assembly name, spaces before the ',' separator are relevant, but spaces after the ',' separator are ignored.
The name of a generic type ends with a backtick (`) followed by digits representing the number of generic type arguments. The purpose of this name mangling is to allow compilers to support generic types with the same name but with different numbers of type parameters, occurring in the same scope. For example, reflection returns the mangled names Tuple`1
and Tuple`2
from the generic methods Tuple(Of T)
and Tuple(Of T0, T1)
in Visual Basic, or Tuple<T>
and Tuple<T0, T1>
in Visual C#.
For generic types, the type argument list is enclosed in brackets, and the type arguments are separated by commas. For example, a generic Dictionary<TKey,TValue> has two type parameters. A Dictionary<TKey,TValue> of MyType
with keys of type String might be represented as follows:
System.Collections.Generic.Dictionary`2[System.String,MyType]
To specify an assembly-qualified type within a type argument list, enclose the assembly-qualified type within brackets. Otherwise, the commas that separate the parts of the assembly-qualified name are interpreted as delimiting additional type arguments. For example, a Dictionary<TKey,TValue> of MyType
from MyAssembly.dll, with keys of type String, might be specified as follows:
Type.GetType("System.Collections.Generic.Dictionary`2[System.String,[MyType,MyAssembly]]")
Note
An assembly-qualified type can be enclosed in brackets only when it appears within a type parameter list. The rules for searching assemblies for qualified and unqualified types in type parameter lists are the same as the rules for qualified and unqualified nongeneric types.
Nullable types are a special case of generic types. For example, a nullable Int32 is represented by the string "System.Nullable`1[System.Int32]".
Note
You can also get nullable types using type operators. For example, the nullable Boolean type is returned by typeof(Nullable<bool>)
in C# and by GetType(Nullable(Of Boolean))
in Visual Basic.
The following table shows the syntax you use with GetType
for various types.
Type.GetType("System.Nullable`1[System.Int32]")
An unmanaged pointer to MyType
Type.GetType("MyType*")
An unmanaged pointer to a pointer to MyType
Type.GetType("MyType**")
A managed pointer or reference to MyType
Type.GetType("MyType&")
. Note that unlike pointers, references are limited to one level. A parent class and a nested class Type.GetType("MyParentClass+MyNestedClass")
A one-dimensional array with a lower bound of 0 Type.GetType("MyArray[]")
A one-dimensional array with an unknown lower bound Type.GetType("MyArray[*]")
An n-dimensional array A comma (,) inside the brackets a total of n-1 times. For example, System.Object[,,]
represents a three-dimensional Object
array. A two-dimensional array's array Type.GetType("MyArray[][]")
A rectangular two-dimensional array with unknown lower bounds Type.GetType("MyArray[,]")
A generic type with one type argument Type.GetType("MyGenericType`1[MyType]")
A generic type with two type arguments Type.GetType("MyGenericType`2[MyType,AnotherType]")
A generic type with two assembly-qualified type arguments Type.GetType("MyGenericType`2[[MyType,MyAssembly],[AnotherType,AnotherAssembly]]")
An assembly-qualified generic type with an assembly-qualified type argument Type.GetType("MyGenericType`1[[MyType,MyAssembly]],MyGenericTypeAssembly")
A generic type whose type argument is a generic type with two type arguments Type.GetType("MyGenericType`1[AnotherGenericType`2[MyType,AnotherType]]")
See also
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