1. 사용방법 using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; namespace SelectAll { public partial class frmSelectAll : Form { int TotalCheckBoxes = 0; int TotalCheckedCheckBoxes = 0; CheckBox HeaderCheckBox = null; bool IsHeaderCheckBoxClicked = false; public frmSele..