C# Signature:

[DllImport("user32.dll")]
static extern bool GetComboBoxInfo(ref COMBOBOXINFO pcbi);

User-Defined Types:

COMBOBOXINFO

Notes:

None.

Tips & Tricks:

Please add some!

Sample Code:

COMBOBOXINFO cbi = new COMBOBOXINFO();
cbi.cbSize = System.Runtime.InteropServices.Marshal.SizeOf(cbi);
if(GetComboBoxInfo(comboBox1.Handle, ref cbi)) {
    if(info.hwndEdit == IntPtr.Zero) {
        throw new Exception("ComboBox must have the DropDown style!");
    }
}

Alternative Managed API:

Do you know one? Please contribute it!