Object Reference Not set to an instance error after deploying the code [duplicate]

Question

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What is a NullReferenceException, and how do I fix it? (26 answers)

Closed 9 years ago.

I am using asp.net GridView for displaying data, I have 9 columns coming from Database,from which I have to hide last two columns and records of those. I am using GridView RowDatabound event for hiding the columns and records. Its working fine when I am running my application from VS, even when I publish it on local IIS, it is working fine, but when I deployed it live, its giving following exception:

Object reference not set to an instance

I am using same database for both publishes Here's my code

        <asp:GridView ID="GridView1" runat="server" OnRowDataBound="GridView1_RowDataBound">
                                </asp:GridView>




        protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
        {
            if (e.Row.RowType == DataControlRowType.DataRow)
            {

                GridView1.HeaderRow.Cells[7].Visible = false;
                GridView1.HeaderRow.Cells[8].Visible = false;
                e.Row.Cells[7].Visible = false;
                e.Row.Cells[8].Visible = false;               
            }
        }

Databinding is done with DataTable

     var data = MyClass.GetHistory();//it returns DataTable
     GridView1.DataSource = data;
     GridView1.DataBind();

Answer 1

If I am correct, you are trying to hide columns 7 and 8, then do it after you bound the datasource as,

GridView1.Columns[7].Visible = false;
GridView1.Columns[8].Visible = false;