private void LaunchGUITool(object sender, EventArgs e)
{
var srcPath = SelectedItemPaths.ElementAtOrDefault(0);
var dstPath = SelectedItemPaths.ElementAtOrDefault(1);
var arg = !string.IsNullOrEmpty(srcPath) ? $"-s \"{srcPath}\" " : string.Empty;
arg += !string.IsNullOrEmpty(dstPath) ? $"-d \"{dstPath}\" " : string.Empty;
string exePath = Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), "ExcelMerge.GUI.exe");
System.Diagnostics.Process.Start(exePath, arg);
}