onchange event for cascading dropdownlist

this script for CourseFun change event

this sript for ACanChange()

Select

protected void Page_Load(object sender, EventArgs e)

{

if (!IsPostBack)

{

course.AppendDataBoundItems = true;

String strConnString = ConfigurationManager.ConnectionStrings["dbconnectionstr"].ConnectionString;

String strQuery = "select Courseid, CourseName from CourseName";

SqlConnection con = new SqlConnection(strConnString);

SqlCommand cmd = new SqlCommand();

cmd.CommandType = CommandType.Text;

cmd.CommandText = strQuery;

cmd.Connection = con;

{

con.Open();

course.DataSource = cmd.ExecuteReader();

course.DataTextField = "CourseName";

course.DataValueField = "Courseid";

course.DataBind();

con.Close();

}

protected void course_SelectedIndexChanged(object sender, EventArgs e)

{

ACan.Items.Clear();

ACan.Items.Add(new ListItem("--Select--", ""));

ACan.AppendDataBoundItems = true;

String strConnString = ConfigurationManager.ConnectionStrings["dbconnectionstr"].ConnectionString;

String strQuery = "select ACanid, ACanName from ACanName " + "where Courseid=@Courseid";

SqlConnection con = new SqlConnection(strConnString);

SqlCommand cmd = new SqlCommand();

cmd.Parameters.AddWithValue("@Courseid", course.SelectedItem.Value);

cmd.CommandType = CommandType.Text;

cmd.CommandText = strQuery;

cmd.Connection = con;

con.Open();

ACan.DataSource = cmd.ExecuteReader();

ACan.DataTextField = "ACanName";

ACan.DataValueField = "Acanid";

ACan.DataBind();

con.Close();

}

code of aspx.cs page

my problem:- if i select course id from first dropdownlist... then show all div according to condition but cascading dropdown list is not working not data show in second dropdownlist then second onchange event will not work

plz some help me.... thanking you

2 Replies

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Dilip Gupta8y ago
Accepted answer
Did you get any error? debug the code to check the problem

For cascading dropdown list you can refer the following link :
https://www.aspsnippets.com/Articles/Populate-Cascading-DropDownList-from-Database-in-ASPNet-Example.aspx
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Ankita Singh8y ago
no.. i didn't got any type of error.... ater use of breakpoint bind of data properly but not hit second dropdown list.... also i take help of this link... before use of onchange event its work properly but after onchange event not hit of the second dropdwn list
0