Send values from other controls to User Control properties in .aspx page

Question

Is there a way pass values from other controls (e.g. "selected value of dropdownlist", "value from query string") to a User Control using a property within the tag itself and NOT from the code behind?

Answer 1

Yes you can, you just need to use the <% %> in the presentation code. Your code would look something like this:

<asp:DropDownList id="ddlFoo" runat="server">
    ...
</asp:DropDownList>
<asp:TextBox id="txtBar" runat="server" Text='<%# ddlFoo.SelectedValue %>' />

<%-- For query string --%>
<asp:TextBox id="txtBar" runat="server" 
    Text='<%# Request.QueryString["Key_Value"] %>' />

The SO post In ASP.Net, what is the difference between <%= and <%# gives a good listing of the different binding mechanisms you can use.

Answer 2

Yes it is. For example

 <uc1:CompetitionClassification ID="CompetitionClassification" runat="server" OnlyTopFive="True" />

in this case, the parameter OnylTopFive is passed within tag of my custom control.

then in server side of my control, i have :

private bool onlyTopFive;
  public bool OnlyTopFive
    {
        get
        {
            return this.onlyTopFive;
        }
        set
        {
            this.onlyTopFive = value;
        }
    }