Marshal.PtrToStringBSTR Method
Allocates a managed String and copies a BSTR string stored in unmanaged memory into it.
[Visual Basic] Public Shared Function PtrToStringBSTR( _ ByVal ptr As IntPtr _ ) As String [C#] public static string PtrToStringBSTR( IntPtr ptr ); [C++] public: static String* PtrToStringBSTR( IntPtr ptr ); [JScript] public static function PtrToStringBSTR( ptr : IntPtr ) : String;
Parameters
- ptr
- The address of the first character of the unmanaged string.
Return Value
A managed string that holds a copy of the native string.
Exceptions
| Exception Type | Condition |
|---|---|
| ArgumentNullException | ptr is a null reference (Nothing in Visual Basic). |
Remarks
Only call this method on strings allocated with the unmanaged SysAllocString and SysAllocStringLen functions.
PtrToStringBSTR 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. This method provides the opposite functionality of Marshal.StringToBSTR.
Note 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.
Requirements
Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family
.NET Framework Security:
- SecurityPermission for operating with unmanaged code. Associated enumeration: SecurityPermissionFlag.UnmanagedCode.
See Also
Marshal Class | Marshal Members | System.Runtime.InteropServices Namespace | StringToBSTR