Use jQuery to change a second select list based on the first select list option

Answer 1

Try to use it:

Drop-down box dependent on the option selected in another drop-down box. Use jQuery to change a second select list based on the first select list option.

    Service
    
    


    Offer
    
    

Use jQuery library in your web page.

Use Backend code in your web page.

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        ServiceList();
    }
}

public void ServiceList()
{
    ManageReport manageReport = new ManageReport();
    DataTable ServiceList = new DataTable();
    ServiceList = manageReport.GetServiceList();
    ddlService.DataSource = ServiceList;
    ddlService.DataTextField = "serviceName";
    ddlService.DataValueField = "serviceId";
    ddlService.DataBind();
    ddlService.Items.Insert(0, new ListItem("All", "0"));
}

public DataTable GetServiceList()
{
    SqlParameter[] PM = new SqlParameter[]
    {
        new SqlParameter("@Mode"    ,"Mode_Name"    ),
        new SqlParameter("@UserID"  ,UserId         )
    };
    return SqlHelper.ExecuteDataset(new SqlConnection(SqlHelper.GetConnectionString()), CommandType.StoredProcedure, "Sp_Name", PM).Tables[0];
}

[WebMethod]
public static String GetOfferList(int UserId, String ServiceId)
{
    var sOfferList = "";
    try
    {
        CommonUtility utility = new CommonUtility();
        ManageReport manageReport = new ManageReport();
        manageReport.UserId = UserId;
        manageReport.ServiceId = ServiceId;
        DataSet dsOfferList = manageReport.GetOfferList();
        if (utility.ValidateDataSet(dsOfferList))
        {
            //DataRow dr = dsEmployerUserDepartment.Tables[0].NewRow();
            //dr[0] = "0";
            // dr[1] = "All";
            //dsEmployerUserDepartment.Tables[0].Rows.InsertAt(dr, 0);
            sOfferList = utility.ConvertToJSON(dsOfferList.Tables[0]);
        }
        return sOfferList;
    }
    catch (Exception ex)
    {
        return "Error Message: " + ex.Message;
    }
}

public DataSet GetOfferList()
{
    SqlParameter[] sqlParameter = new SqlParameter[]
        {                                                                     
            new SqlParameter("@Mode"        ,"Mode_Name"    ),
            new SqlParameter("@UserID"      ,UserId         ),
            new SqlParameter("@ServiceId"   ,ServiceId      )
        };
    return SqlHelper.ExecuteDataset(new SqlConnection(SqlHelper.GetConnectionString()), CommandType.StoredProcedure, "Sp_Name", sqlParameter);
}