Question

I have a templated Gridview where I only want to display one column (Questions — these are database obtained), and the other the dropdownlist of possible answers (Options). The dropdownlist’s values change depending on the type of the question. There are only 2 types: T/F or ranged (Lo, Med, High). So if the question is type 1, the dropdownlist should just display T/F. Likewise if it’s type II.

Shown below is the gridview and the method that loads the dropdownlist (supposedly):

    <asp:GridView AutoGenerateColumns="false" runat="server" ID="SurveyView">
    <Columns>

        <asp:BoundField HeaderText="Questionnaire" DataField="Questionaire" ReadOnly="true"/>
        <asp:BoundField HeaderText="QuestionID" DataField="Id" ReadOnly="true" Visible="false" />
        <asp:BoundField HeaderText="IsBoolean" DataField="Filter" ReadOnly="true" Visible="false" />
        <asp:TemplateField HeaderText="Response">
            <ItemTemplate>
                <asp:DropDownList ID="UserDropDown" runat="server" AppendDataBoundItems="true" DataSource="LoadDropdownList(Filter)" DataTextField="key" DataValueField="value"></asp:DropDownList>
            </ItemTemplate>
        </asp:TemplateField>
    </Columns>
</asp:GridView>


        public Dictionary<String, String> GenerateDropdownList(bool BooleanFilterStatus)
    {
        Dictionary<String, String> tempStores = new Dictionary<string, string>() ; 
        if (BooleanFilterStatus)
        {
            tempStores.Add(Boolean.TrueString, Boolean.TrueString);
            tempStores.Add(Boolean.FalseString, Boolean.FalseString);
        }
        else
        {
            tempStores.Add("NONE", "NIL");
            tempStores.Add("Lo", "Low");
            tempStores.Add("Medium", "Medium");
            tempStores.Add("High", "High"); 
        }

        return tempStores; 
    }

I was hoping that by using LoadDropdownList(), it would be populating the list. But that does not appear to work.

Any ideas or other possible solution would be appreciated.

Answer 1

How about something like

<asp:DropDownList ID="UserDropDown" runat="server" AppendDataBoundItems="true" 
 ondatabinding="DropDownList1_DataBinding" DataTextField="key" DataValueField="value"></asp:DropDownList>

and in code-behind

 protected void DropDownList1_DataBinding(object sender, EventArgs e)
    {
        var ddl = sender as DropDownList;
        if(ddl!=null)
        {
          //populate list. 
          ddl.Items.Add(new ListItem("test"));
        }
    }