当我在我的主组合框中输入新值时，我希望我的另一个组合框检查SQL DB AND auto complete(如果一切就绪

当我试图将新数据输入我的主COMBO框时，我想制作一个触发器来清除我的COMBO BOXS？

这是我的代码，它连接到数据库并从中提取数据，我想知道当我输入新的数据时，我如何根据我的主代码创建一个触发器来清除COMBO BOXS的其余部分

            SqlConnection cn = new SqlConnection("server=CH-PC; integrated security = true ; database = finalproject");
            SqlDataAdapter da = new SqlDataAdapter("select * from books ", cn);
            DataSet ds = new DataSet();
            da.Fill(ds, "books");
            comboBox3.DataSource = ds.Tables["books"];
            comboBox3.DisplayMember = "book_ispn";
        if (comboBox3.DisplayMember != "") {          
            SqlDataAdapter daa = new SqlDataAdapter("select * from books where book_ispn= " + comboBox3.Text, cn);
            DataSet dss = new DataSet();
            da.Fill(dss, "books");
            comboBox4.DataSource = ds.Tables["books"];
            comboBox4.DisplayMember = "book_name";
            SqlDataAdapter daaa = new SqlDataAdapter("select * from books where book_ispn= " + comboBox3.Text, cn);
            DataSet dsss = new DataSet();
            da.Fill(dsss, "books");
            comboBox5.DataSource = ds.Tables["books"];
            comboBox5.DisplayMember = "book_author";
            SqlDataAdapter daaaa = new SqlDataAdapter("select * from books where book_ispn= " + comboBox3.Text, cn);
            DataSet dssss = new DataSet();
            da.Fill(dssss, "books");
            comboBox6.DataSource = ds.Tables["books"];
            comboBox6.DisplayMember = "book_publisher";
            SqlDataAdapter jaa = new SqlDataAdapter("select * from books where book_ispn= " + comboBox3.Text, cn);
            DataSet kss = new DataSet();
            da.Fill(kss, "books");
            comboBox7.DataSource = ds.Tables["books"];
            comboBox7.DisplayMember = "book_edition";
            SqlDataAdapter jaas = new SqlDataAdapter("select * from books where book_ispn= " + comboBox3.Text, cn);
            DataSet ksas = new DataSet();
            da.Fill(ksas, "books");
            comboBox1.DataSource = ds.Tables["books"];
            comboBox1.DisplayMember = "school_name";
            SqlDataAdapter jasas = new SqlDataAdapter("select * from books where book_ispn= " + comboBox3.Text, cn);
            DataSet ksaas = new DataSet();
            da.Fill(ksaas, "books");
            comboBox2.DataSource = ds.Tables["books"];
            comboBox2.DisplayMember = "major_code";
        }

$("#<%= comboBox3.ID %>").on("change", function(){
    $("#<%= comboBox4.ID %>").val('');
    $("#<%= comboBox5.ID %>").val('');
    $("#<%= comboBox6.ID %>").val('');
    ....
});