Check asp.net checkboxlist using Jquery

Question

I am using a [webmethod] to retrieve a list of strings from sql-server. the code is :

[WebMethod]
public void SelectActivityCheckboxItems(int SystemID)
    {
    //Configure a connection to SystemRegister database        
        var cs = ConfigurationManager.ConnectionStrings["SYSTEMREGISTERConnectionString"].ConnectionString;
        List<string> SelectedActivity = new List<string>();
        //Get the related data for update activty checkbox 
        using (var con = new SqlConnection(cs))
        {                
            con.Open();
            var cmd = new SqlCommand("setModalSystemUpdate", con) { CommandType = CommandType.StoredProcedure };
            cmd.Parameters.AddWithValue("@SYSTEMID", SystemID);
            var dr = cmd.ExecuteReader();
            while (dr.Read())
            {
                SelectedActivity.Add(dr[0].ToString());
            }
            con.Close();
        }
        var js = new JavaScriptSerializer();
        Context.Response.Write(js.Serialize(SelectedActivity));   
}

Here is the checkboxlist:

 <div class="scroll">
                        <fieldset class="form-group">
                            <label class="col-sm-3">Aktivitet:</label>
                            <div>
                                <asp:CheckBoxList CssClass="paddingright" ID="CheckBoxListActivityUpdate" runat="server"
                                    DataSourceID="SqlDataSource6"
                                    DataValueField="ACTIVITYNAME"
                                    RepeatColumns="2">                                       
                                </asp:CheckBoxList>
                            </div>
                        </fieldset>
                    </div>

In my aspx I have this Jquery to "check" the items that are in the list and exist in the checkboxlist.

 $.ajax({
                    type: "POST",
                    url: "SystemService.asmx/SelectActivityCheckboxItems",
                    dataType: "json",
                    data: '{Value: "' + $("#<%=rowID.ClientID%>").value + '" }',
                    contentType: "application/json",
                    success: function (data) {
                        $.each(function () {
                            $("#CheckBoxListActivityUpdate").prop('checked', true);
                        })
                    }
                });  

unfortunatly this does not work, is there any other solutions?

Answer 1

$.each(function () { with no input makes no sense. What's the point of that? It won't do anything because there's nothing for it to loop over, so the code inside it will never execute. You can just remove it.

Also you may need to use $("#<%=CheckBoxListActivityUpdate.ClientID%>") if the checkbox is an <asp:Checkbox server control.

Of course if you need to actually use the response data for something, and use it to control whether the box is checked or not, then you'll have to either write that yourself, or clarify the question to say exactly what should happen based on the response data (specify the properties in the data which are relevant and also show the target HTML).

---

As an aside, don't build your data object by hand, instead create a proper object and get the browser to stringify it for you, then you'll avoid any potential syntax errors:

data: JSON.stringify({ "Value": $("#<%=rowID.ClientID%>").value })