for windows Application
string chkVal = checkBox1.CheckState.GetHashCode().ToString()+
checkBox2.CheckState.GetHashCode().ToString()+
checkBox3.CheckState.GetHashCode().ToString()+
checkBox4.CheckState.GetHashCode().ToString()+
checkBox5.CheckState.GetHashCode().ToString();
for web Application
string chkVal = (CheckBox1.Checked ? "1" : "0").ToString() +
(CheckBox2.Checked ? "1" : "0").ToString() +
(CheckBox3.Checked ? "1" : "0").ToString() +
(CheckBox4.Checked ? "1" : "0").ToString() +
(CheckBox5.Checked ? "1" : "0").ToString();
Label1.Text = chkVal;
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