There is a GetWindowText() in user32 API,
but if you need to get text from a control in another process, GetWindowText() won't work.
You have to use SendMessage() with WM_GETTEXT instead:
const UInt32 WM_GETTEXT = 0x000D;
const UInt32 WM_GETTEXTLENGTH = 0x000E;
[DllImport("user32.dll", CharSet = CharSet.Auto)]
static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, IntPtr wParam, IntPtr lParam);
[DllImport("user32.dll", CharSet = CharSet.Auto)]
static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, IntPtr wParam, StringBuilder lParam);
static string GetWindowTextRaw(IntPtr hwnd)
{
// Allocate string length
int length = (int)SendMessage(hwnd, WM_GETTEXTLENGTH, IntPtr.Zero, IntPtr.Zero);
StringBuilder sb = new StringBuilder(length + 1);
// Get window text
SendMessage(hwnd, WM_GETTEXT, (IntPtr)sb.Capacity, sb);
return sb.ToString();
}