Question

I’ve got a really weird problem and I can’t seem to find a solution to it. I’ve got an SqlDataSource with a set of parameters and a select command in form of a stored procedure. One of the parameters is a string called @SearchPhrase which gets its value from a textbox that when left empty is suppose to return all posts. The parameter gets its value via a search button that first set the value of searchBox.Text.Trim() to the @SearchPhrase and then databinds a gridview that displays the search result.

The stored procedure works fine and returns the result as long as a value is entered in the textbox but when left empty it turns out the stored procedure is never executed. I know this because I’ve added a line to it that stores all of the parameters inserted every time it’s called.

How come I can’t get it to run without entering something in the textbox? The only way I can get it to execute is to enter a blank space and pass ” ” to the stored procedure and after that do a left and right trim on it. Why not when passing a string with length = 0?

Here’s the code for the datasource and the assigning of the parameters. It’s only the @SearchPhrase parameter that is causing the problem, the rest work just fine. The first three lines of the click event (the commented) is the somewhat ugly way to go if I want to assign a ” ” and that way make it work.

        <asp:SqlDataSource ID="enterprisesDS" runat="server" 
            ConnectionString="<%$ ConnectionStrings:CRMdb %>" 
            SelectCommand="entGetEnterprises" SelectCommandType="StoredProcedure">

            <SelectParameters>
                <asp:Parameter Name="SearchPhrase" Type="String" />
                <asp:Parameter Name="IsActive" Type="Boolean" DefaultValue="true" />
                <asp:Parameter Name="Country" Type="Byte" />
                <asp:Parameter Name="LocalReference" Type="String" />
                <asp:Parameter Name="Class" Type="String" />
                <asp:Parameter Name="LocationID" Type="Byte" />
            </SelectParameters>

        </asp:SqlDataSource>

        protected void search_Click(object sender, EventArgs e)
    {
        //string searchPhrase = " ";

        //if (searchBox.Text.Trim().Length > 0)
        //    searchPhrase = searchBox.Text.Trim();

        enterprisesDS.SelectParameters["SearchPhrase"].DefaultValue = searchBox.Text;
        enterprisesDS.SelectParameters["Country"].DefaultValue = countries.SelectedValue;
        enterprisesDS.SelectParameters["LocalReference"].DefaultValue = localReferences.SelectedValue;
        enterprisesDS.SelectParameters["Class"].DefaultValue = classes.SelectedValue;

        string locID = "0";
        if (locations.SelectedValue != null)
            locID = locations.SelectedValue;

        enterprisesDS.SelectParameters["LocationID"].DefaultValue = locID;

        enterprises.DataBind();
    }

Answer 1

Could this be it? CancelSelectOnNullParameter property on the SqlDataSource.

SqlDataSource and stored procedure call issue