Question

I am using asp.net 3.5 with C#. I need to do a database lookup when a user enters ProductID in txtProductID. I guess doing javascript is out of the question since this will have to be server side call.
I wrote this code in the page_load event of the webpage:

        protected void Page_Load(object sender, EventArgs e)
    {
        txtProductID.Attributes.Add("onblur", "LookupProduct()");
    }

        protected void LookupProduct()
    {
        //Lookup Product information on onBlur event;
    }

I get an error message: Microsoft JScript runtime error: Object expected
How can I resolve this ?

Answer 1

Use the TextBox.TextChanged event.

ASPX markup:

<asp:TextBox ID="txtProductID" runat="server" AutoPostBack="true" OnTextChanged="txtProductID_TextChanged" />

Codebehind:

protected void txtProductID_TextChanged(object sender, EventArgs e)
{
   // do your database query here
}