asp.net C # byte[] conversion to IntPtr several methods

There are several ways to access the IntPtr that correspond to a byte array.

The first is to use unsafe blocks of code to access pointers that directly point to byte arrays.

The code is as follows	Copy Code
Unsafe { byte[] test = new BYTE[5]; Fixed (byte* p = &test[0]) { *p = 0xFF; } }

Second, you can use GCHandle to get objects.

The code is as follows	Copy Code
Using System.Runtime.InteropServices; byte[] test = new BYTE[5]; GCHandle hobject = GCHandle.Alloc (test, gchandletype.pinned); IntPtr pobject = Hobject.addrofpinnedobject (); if (hobject.isallocated) Hobject.free ();

The third is to create a block of memory through LocalAlloc and marshal the data to the memory block.

The code is as follows

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[DllImport ( "Coredll.dll", Setlasterror=true)] public static extern IntPtr LocalAlloc (UINT uflags, uint ubytes); [DllImport ("Coredll.dll", Setlasterror=true)] public static extern IntPtr LocalFree (IntPtr hmem); [DllImport ("Coredll.dll", Setlasterror=true)] public static extern IntPtr Localrealloc (IntPtr hmem, uint ubytes , uint fuflags); Public const UINT LMEM_FIXED = 0; Public const UINT LMEM_MOVEABLE = 2; Public const UINT LMEM_ZEROINIT = 0x0040; Byte[] test = new BYTE[5]; IntPtr p = LocalAlloc (lmem_fixed | Lmem_zeroinit, (UINT) test. Length); if (p = = IntPtr.Zero) {     throw new OutOfMemoryException (); } Else {     marshal.copy (test, 0, p, test. Length); }