this.checkedListBox1.Items.Clear();
            foreach (char s in "abigcat")
            {
                this.checkedListBox1.Items.Add(s);
            }

            string strValue = "abc";
            for (int i = 0; i < this.checkedListBox1.Items.Count; i++)
            {
                string chkValue = this.checkedListBox1.Items[i].ToString();
                if (strValue.IndexOf(chkValue) >= 0)
                {
                    this.checkedListBox1.SetItemChecked(i, true);
                }
            }