This documentation is archived and is not being maintained.

Marshal.PtrToStringAuto Method (IntPtr)

Allocates a managed String and copies all characters up to the first null character from a string stored in unmanaged memory into it.

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

[SecurityPermissionAttribute(SecurityAction.LinkDemand, Flags = SecurityPermissionFlag.UnmanagedCode)]
public static string PtrToStringAuto(
	IntPtr ptr
)

Parameters

ptr
Type: System.IntPtr

For Unicode platforms, the address of the first Unicode character.

-or-

For ANSI plaforms, the address of the first ANSI character.

Return Value

Type: System.String
A managed string that holds a copy of the unmanaged string if the value of the ptr parameter is not null; otherwise, this method returns null.

If the current platform is Unicode, each ANSI character is widened to a Unicode character and this method calls PtrToStringUni. Otherwise this method calls PtrToStringAnsi.

PtrToStringAuto is useful for custom marshaling or when mixing managed and unmanaged code. Since this method creates a copy of the unmanaged string's contents, you must free the original string as appropriate. PtrToStringAnsi provides the opposite functionality of Marshal.StringToCoTaskMemAuto and Marshal.StringToHGlobalAuto.

NoteNote:

This method uses SecurityAction.LinkDemand to prevent it from being called from untrusted code; only the immediate caller is required to have SecurityPermissionAttribute.UnmanagedCode permission. If your code can be called from partially trusted code, do not pass user input to Marshal class methods without validation. For important limitations on using the LinkDemand member, see Demand vs. LinkDemand.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0
Show: