Object reference not set to an instance of an object

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This is my code

error occure in this line

C#

string query = "UPDATE [WebCrm].[dbo].[tbl_Lead] SET FirstName='" + textLead.Text + "',Date='" + textDate.Text + "',Status='" + textStatus.Text + "',PotentialRevenue='" + textRevenue.Text + "',ProductInterest='" + textProduct.Text + "',Owner='" + textOwner.Text + "',Company='" + textCompany.Text + "' where LedId='" + Convert.ToInt32(lblLedId.Text) + "'";

C#

protected void grdLead_RowUpdating(object sender, GridViewUpdateEventArgs e)
       {
           SqlConnection con = new SqlConnection(cn.ConnectionStrings);
           Label lblLedId = (Label)grdLead.FindControl("lblLedId");
           TextBox textLead = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textLead");
           TextBox textCompany = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textCompany");
           TextBox textProduct = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textProduct");
           TextBox textRevenue = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textRevenue");
           TextBox textDate = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textDate");
           TextBox textStatus = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textStatus");
           TextBox textOwner = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textOwner");
           string query = "UPDATE [WebCrm].[dbo].[tbl_Lead] SET FirstName='" + textLead.Text + "',Date='" + textDate.Text + "',Status='" + textStatus.Text + "',PotentialRevenue='" + textRevenue.Text + "',ProductInterest='" + textProduct.Text + "',Owner='" + textOwner.Text + "',Company='" + textCompany.Text + "' where LedId='" + Convert.ToInt32(lblLedId.Text) + "'";
           con.Open();
           SqlCommand cmd = new SqlCommand(query,con);
           cmd.CommandType = CommandType.Text;
           cmd.ExecuteNonQuery();
           con.Close();
           grdLead.EditIndex = -1;
           bindLead();

UPDATE: Code from repost:

XML

<asp:GridView ID="grdLead" DataKeyNames="LedId" runat="server" AllowPaging="True" AllowSorting="True" CssClass="table table-bordered" AutoGenerateColumns="False" EnableModelValidation="True" CellPadding="0" GridLines="None" Width="100%" ShowFooter="True" OnPageIndexChanging="grdLead_PageIndexChanging" OnRowCancelingEdit="grdLead_RowCancelingEdit" OnRowDeleting="grdLead_RowDeleting" OnRowEditing="grdLead_RowEditing" OnRowUpdating="grdLead_RowUpdating">
                              <Columns>
                                  <asp:BoundField DataField="LedId" HeaderText="Sr.No"  />
                                  <asp:BoundField DataField="FirstName" HeaderText="Lead Name"/>
                                  <asp:BoundField DataField="Date" HeaderText="Date"  />
                                  <asp:BoundField DataField="Status" HeaderText="Status"  />
                                  <asp:BoundField DataField="PotentialRevenue" HeaderText="PotentailRevenuer" />
                                  <asp:BoundField DataField="ProductInterest" HeaderText="ProductInterest"  />
                                  <asp:BoundField DataField="Owner" HeaderText="Owner" />
                                  <asp:BoundField DataField="Company" HeaderText="CompanyName"  />
                                  <asp:CommandField ShowEditButton="True"  />
                                  <asp:CommandField ShowDeleteButton="True"/>
                              </Columns>
                          </asp:GridView>

Posted 15-Oct-15 22:09pm

Radhika20

Updated 15-Oct-15 23:42pm

Andy Lanng

v3

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Andy Lanng 16-Oct-15 5:42am

You don't need to repost. It really rubs people the wrong way.

You can use the "Improve Question" button above this comment to add detail. I'll add the ASP for you

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Andy Lanng · Answer 1 · 2015-10-15T22:25:00

First off: You should never build queries with parameter injection. This leaves you wide open to SQL injection attacks which can destroy your data. Use parameterized queries instead. This will also help you find the problem:

C#

//No need to generate the query string every time.
private const string query1 = @"
UPDATE [WebCrm].[dbo].[tbl_Lead] 
SET FirstName=@firstname, 
    Date=@date, 
    Status=@status,
    PotentialRevenue=@revenue,
    ProductInterest=@interest,
    Owner=@owner,
    Company=@company 
where LedId=@ledId";

protected void grdLead_RowUpdating(object sender, GridViewUpdateEventArgs e)
       {
           SqlConnection con = new SqlConnection(cn.ConnectionStrings);
           Label lblLedId = (Label)grdLead.FindControl("lblLedId");
           TextBox textLead = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textLead");
           TextBox textCompany = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textCompany");
           TextBox textProduct = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textProduct");
           TextBox textRevenue = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textRevenue");
           TextBox textDate = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textDate");
           TextBox textStatus = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textStatus");
           TextBox textOwner = (TextBox)grdLead.Rows[e.RowIndex].FindControl("textOwner");
           string query = query1; 

            SqlCommand cmd = new SqlCommand(query, con);
            cmd.CommandType = CommandType.Text;
            cmd.Parameters.Add(new SqlParameter("@firstname", SqlDbType.NVarChar) { Value = textLead.Text });
            //You can specify different datatypes if you need to:
            cmd.Parameters.Add(new SqlParameter("@date", SqlDbType.Date) { Value = textDate.Text });
            cmd.Parameters.Add(new SqlParameter("@status", SqlDbType.NVarChar) { Value = textStatus.Text });
            cmd.Parameters.Add(new SqlParameter("@revenue", SqlDbType.NVarChar) { Value = textRevenue.Text });
            cmd.Parameters.Add(new SqlParameter("@interest", SqlDbType.NVarChar) { Value = textProduct.Text });
            cmd.Parameters.Add(new SqlParameter("@owner", SqlDbType.NVarChar) { Value = textOwner.Text });
            cmd.Parameters.Add(new SqlParameter("@company", SqlDbType.NVarChar) { Value = textCompany.Text });
            cmd.Parameters.Add(new SqlParameter("@ledId", SqlDbType.Int) { Value = lblLedId.Text });

           
           con.Open(); //only open the connection when you're ready to execute
           int rowsChanged = cmd.ExecuteNonQuery();
           con.Close();
           //if(rowsChanged==1)
             //success
           //else
             //failure
           grdLead.EditIndex = -1;
           bindLead();

Use that and you will see exactly where the error is.

PS: one of your controls was not found ^_^

UPDATE: You can simplify the method as so:

C#

protected void grdLead_RowUpdating(object sender, GridViewUpdateEventArgs e)
       {
           SqlConnection con = new SqlConnection(cn.ConnectionStrings);
           Label lblLedId = (Label)grdLead.FindControl("lblLedId");
           TextBox textLead = (TextBox)e.Row.FindControl("textLead");
           TextBox textCompany = (TextBox)e.Row..FindControl("textCompany");
           TextBox textProduct = (TextBox)e.Row..FindControl("textProduct");
           //Etc...

I'll keep looking into the root issue