[C#]將數字前面補0，補足設定的長度

// 將數字前面補0，補足長度為6 
String snum = "123"; 
String pnum = snum.PadLeft(6, '0'); 
String fnum = String.Format("...{0:000000}",Convert.ToInt16(snum)); 
MessageBox.Show( "原始字串 : " + snum + "\n 透過 PadLeft : " + pnum + "\n 透過 String.Format : " + fnum);