C++ Equivalent to VB ReDim Preserve

Resizing arrays while preserving the existing contents is easily done in VB using ReDim Preserve. In C++/CLI, you have other alternatives:

Use one of the existing .NET collections, such as ArrayList or the generic List, that handle dynamic resizing automatically.
If the array has only one dimension then you can use the Array.Resize method.
For multi-dimensional arrays, use the same logic that VB executes behind the scenes for a ReDim Preserve:

VB:
ReDim Preserve YourArray(1, 2)

C++/CLI (assuming an integer array):
array<int, 2> ^tempReDim1 = gcnew array<int, 2>(2,3);
if (YourArray != nullptr)
{
    for (int Dim0 = 0; Dim0 < YourArray->GetLength(0); Dim0++)
    {
        int CopyLength = System::Math::Min(YourArray->GetLength(1), tempReDim1->GetLength(1));
        for (int Dim1 = 0; Dim1 < CopyLength; Dim1++)
        {
            tempReDim1[Dim0, Dim1] = YourArray[Dim0, Dim1];
        }
    }
}

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