protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { //綁定DropDownList1 SqlConnection con = new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings["wj"]); con.Open(); SqlCommand cmd = new SqlCommand("select * from tezheng ", con); SqlDataReader reader = cmd.ExecuteReader(); DropDownList1.DataSource = reader; DropDownList1.DataTextField = "name"; DropDownList1.DataValueField = "id"; DropDownList1.DataBind(); reader.Close(); //綁定DropDownList2 SqlCommand cmd2 = new SqlCommand("select * from tezheng1 where id="+this.industry.SelectedValue, con); reader = cmd2.ExecuteReader();//上面定義過reader,這里就不用從新定義 DropDownList2.DataSource = reader; DropDownList2.DataTextField = "tname"; DropDownList2.DataValueField = "tid"; DropDownList2.DataBind(); reader.Close(); } protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e) { //DropDownList1與DropDownList2數(shù)據(jù)綁定的聯(lián)動性 string id = this.DropDownList1.SelectedValue; SqlConnection con = new SqlConnection(System.Configuration.ConfigurationSettings.AppSettings["wj"]); con.Open(); SqlCommand cmd = new SqlCommand("select * from tezheng1 where id="+id,con); SqlDataReader reader = cmd.ExecuteReader(); this.DropDownList2.DataSource = reader; this.DropDownList2.DataTextField = "tname"; this.DropDownList2.DataValueField = "tid"; this.DropDownList2.DataBind(); reader.Close(); con.Close(); } ![]() |
|