c# DataTable Adding Data from Table

Question

I have a datatable being populated however one of the fields is a drop down list which is derived from a database connection. When I click add it always add the same data despite my selection and then removes the first item in the list.

ASPX Code

<asp:TableCell><asp:DropDownList runat="server" ID="txtProduct"></asp:DropDownList></asp:TableCell>

CS Code for Dropdown List

public void Fill1()
{
    string connectionString = WebConfigurationManager.ConnectionStrings["CRM2Sage"].ConnectionString;
    using (SqlConnection _con = new SqlConnection(connectionString))
    using (SqlCommand cmd = new SqlCommand("SELECT * FROM Products", _con))
    {
        cmd.Connection.Open();

        SqlDataReader ddlValues;
        ddlValues = cmd.ExecuteReader();

        txtProduct.DataSource = ddlValues;
        txtProduct.DataValueField = "Description";
        txtProduct.DataTextField = "Description";
        txtProduct.DataBind();

        cmd.Connection.Close();
        cmd.Connection.Dispose();
    }
}

Any thoughts as to how to fix this?

A sidenote: you are naming a DropDownList txtProduct? I would assume that a control with this ID is a Textbox. To your question: are you binding the DropDownList only if !Page.IsPostBack? — Tim Schmelter
– Tim Schmelter, Commented Mar 30, 2011 at 16:10
I think you'll find that the call to DataBind resets your selection to the first item. — Jim Mischel
– Jim Mischel, Commented Mar 30, 2011 at 16:19
Also, there's no reason to call cmd.Connection.Close and cmd.Connection.Dispose, since you have the command and the connection in using blocks. They'll be disposed automatically. — Jim Mischel
– Jim Mischel, Commented Mar 30, 2011 at 16:20
I having a hard time understanding what you mean by "When I click add it always add the same data despite my selection and then removes the first item in the list." Can you please expand on this some more. — Evan Larsen
– Evan Larsen, Commented Mar 30, 2011 at 16:21

Muhammad Akhtar · Accepted Answer · 2011-03-30 17:53:34Z

1

I think you are calling Fill1() method in page load. When page is PostBack then in page load event Fill1() again called and your selection will be cleared. you need to this in your load event

if(!Page.IsPostBack)
{
   Fill1();
}

answered Mar 30, 2011 at 17:53

Muhammad Akhtar

52.2k37 gold badges142 silver badges191 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

Steve Wellens · Accepted Answer · 2011-03-30 16:45:27Z

0

I think you are missing the WHERE part of your SQL statement and a way to connect the DropDownList selection to the SQL Statment. Something like...

new SqlCommand("SELECT * FROM Products WHERE ProductID = " + txtProduct.SelectedValue , _con))

FYI: This is for illustration only, I would never put two steps in one line of code, I would use parameters and I would add a boat load of error checking.

answered Mar 30, 2011 at 16:45

Steve Wellens

20.6k2 gold badges31 silver badges70 bronze badges

1 Comment

Justin Erswell Over a year ago

I have no Id to do this with i Have a ProductCode would that do the same job?

Collectives™ on Stack Overflow

c# DataTable Adding Data from Table

2 Answers 2

Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related