Managed C++/CLI

// Following line is wrong. pDataByte is an object with type as System.Array. 
// You can't cast it as unsigned char
QByte[0] = (unsigned char)System::Convert::ToChar(pDataByte); 

// Getting unsigned array from pDataByte
array<unsigned char>^ uChars = static_cast<array<unsigned char>^>(pDataByte);

// filling QByte
for(int i=0; i < uChars->Length; i++)
{
    QByte[i] = uChars[i];
}

array<unsigned char>^ uChars = static_cast<array<unsigned char>^>(pDataByte);
System::Runtime::InteropServices::Marshal::Copy(uChars, 0, System::IntPtr(QByte), 4);

Thank you both extremely much

Luc Pattyn wrote:

three people working as a team should be sufficient to move 4 bytes

marcusab wrote:

I would like to copy the data content of pDataByte to QByte

array<Byte> ^pDataByte = gcnew array<Byte>(4);
pDataByte[0] = 0x41;
pDataByte[1] = 0x42;
pDataByte[2] = 0x43;
pDataByte[3] = 0x44;

unsigned char QByte[4];

// Use a pinning pointer
pin_ptr<Byte> p = &pDataByte[0];
memcpy(QByte, p, 4);

// Use Marsal.Copy()
Marshal::Copy(pDataByte, 0, IntPtr(QByte), 4);

Mark Salsbery
Microsoft MVP - Visual C++

Thank you very very very much , you got me going in the right direction, see my answer to Navaneeth for more info.

Name         Value           Type
pDataByte    {System.Array}  System::Object^
 [0x0]       0x41 ‘A’        unsigned char
 [0x1]       0x42 ‘B’        unsigned char
 [0x2]       0x43 ‘C’        unsigned char
 [0x3]       0x44 ‘D’        unsigned char
QByte        {Length=0x4}    unsigned char[]
 [0x0]       0x00 ‘’         unsigned char
 [0x1]       0x00 ‘’         unsigned char
 [0x2]       0x00 ‘’         unsigned char
 [0x3]       0x00 ‘’         unsigned char

<br />
error C2665: 'System::Runtime::InteropServices::Marshal::Copy' : none of the 16 overloads could convert all the argument types<br />

marcusab wrote:

pDataByte is a System::Object^ {System.Array}, not an array

Mark Salsbery
Microsoft MVP - Visual C++

System::Object ^pDataByte = gcnew System::Object(System::Array<<System::Byte>>(4));

Name         Value           Type
pDataByte    {System.Array}  System::Object^
 [0x0]       0x00 ‘’         unsigned char
 [0x1]       0x00 ‘’         unsigned char
 [0x2]       0x00 '’         unsigned char
 [0x3]       0x00 ‘’         unsigned char

array<Byte> ^pDataByte = gcnew array<Byte>(4);

System::Object ^pDataByte = gcnew array<Byte>(4);

Mark Salsbery
Microsoft MVP - Visual C++

J_E_D_I wrote:

I can't understand how I can pass different values to the main form (form1) when each button is selected.

Mark Salsbery
Microsoft MVP - Visual C++

J_E_D_I wrote:

but I can't understand how I can pass different values to the main form (form1) when each button is selected.