Marshal.StringToCoTaskMemUni Method (String)


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Copies the contents of a managed String to a block of memory allocated from the unmanaged COM task allocator.

Namespace:   System.Runtime.InteropServices
Assembly:  mscorlib (in mscorlib.dll)

Public Shared Function StringToCoTaskMemUni (
	s As String
) As IntPtr


Type: System.String

A managed string to be copied.

Return Value

Type: System.IntPtr

An integer representing a pointer to the block of memory allocated for the string, or 0 if s is null.

Exception Condition

The s parameter exceeds the maximum length allowed by the operating system.


There is insufficient memory available.

StringToCoTaskMemUni is useful for custom marshaling or for use when mixing managed and unmanaged code. Because this method allocates the unmanaged memory required for a string, always free the memory by calling Marshal.FreeCoTaskMem. This method provides the opposite functionality of Marshal.PtrToStringUni. The characters of the string are copied as Unicode characters.


requires full trust for the immediate caller. This member cannot be used by partially trusted or transparent code.

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Windows Phone
Available since 8.1
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