private void button1_Click( object sender , EventArgs e)
{
string output = string . Empty;
for ( int i = 0 ; i < checkedListBox1 . CheckedIndices . Count; i ++ )
{
output += checkedListBox1 . Items[
checkedListBox1 . CheckedIndices[i]] . ToString() + "\r\n" ;
}
MessageBox . Show(output);
}