private void button4_Click(object sender, EventArgs e)
{
string myDocspath = this.textBoxRecordDirectory.Text;
string windir = Environment.GetEnvironmentVariable("WINDIR");
System.Diagnostics.Process prc = new System.Diagnostics.Process();
prc.StartInfo.FileName = windir + @"\explorer.exe";
prc.StartInfo.Arguments = myDocspath;
prc.Start();
}