Update in C# using SQL Server Database.

[Norris Chappell]

I have a datagridview that I changed the name Jones to Brown in a row. Now I need to update my SqlServer table with that change. I am using C# for the code and SqlServer 2010 for the database and SharePoint to display the data as a webpart. I have read almost everything on the internet and can't seem to find an answer to my issue. Datagridview KeyPer Test Name Doe Smith Jones I change a name in the Name column KeyPer Test Name Doe Smith brown I'm having trouble getting past this setting of the parameter for ID. It is giving me am error: The name ID does not exist in the current content. Code Behind

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.Sql;
using System.Data.SqlClient;
using System.Configuration;
using System.Data;

namespace StaffingWebParts.KeyPerTest
{
public partial class KeyPerTestUserControl : UserControl
{
SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["SQLStaffingConn"].ConnectionString);
SqlCommand cmd = new SqlCommand();
protected void Page_Load(object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
DataTable dt = new DataTable();

            dt.Columns.Add("Name");
            dt.Columns.Add("VDCIDIQ");
            dt.Columns.Add("VDCFFS");
            dt.Columns.Add("VDCHIM");
            dt.Columns.Add("VDCWEBHOSTING");
            dt.Columns.Add("VDCCWF");
            SqlDataReader myReader = null;
            SqlCommand cmd = new SqlCommand("SELECT distinct  Name, VDCIDIQ , VDCFFS, VDCHIM, VDCWEBHOSTING, VDCCWF  from CMS\_Key\_Personnel where Name <> '   ' order by  Name");
            cmd.Connection = conn;
            conn.Open();
            myReader = cmd.ExecuteReader();
            while (myReader.Read())
            {
                DataRow dr = dt.NewRow();
                dr\[0\] = myReader\["Name"\].ToString();
                dr\[1\] = myReader\["VDCIDIQ"\].ToString();
                dr\[2\] = myReader\["VDCFFS"\].ToString();
                dr\[3\] = myReader\["VDCHIM"\].ToString();
                dr\[4\] = myReader\["VDCWEBHOSTING"\].ToString();
                dr\[5\] = myReader\["VDCCWF"\].ToString();

[Agent__007]

Look at this line:

cmd.Parameters.Add("@id", SqlDbType.Int).Value = id;

What is "id" (on the RHS of that assignment statement) here? I think that should be it. -- EDIT I don't see any "ID" column you are fetching while binding the data to the grid. So, I am not sure from where you will be using that in your SQL statement. Perhaps a label or something else somewhere on the page? :~

You have just been Sharapova'd.

[Norris Chappell]

The id is the [ID] [int] IDENTITY(1,1) NOT NULL, field. Do I need to show it on my datgridview?

[Norris Chappell]

When I use this code cmd.Parameters.Add("@id", SqlDbType.Int).Value = id; I am getting this error: The name 'id' does not exist in the current context

[Agent__007]

Norris Chappell wrote:

I am getting this error: The name 'id' does not exist in the current context

Yes, that's what I was referring to. You don't have a variable "id" from which you are assigning your "@ID" parameter a value. Even though your "ID" is an identity column, you will still need its value in order to execute your UPDATE query. How else will you be uniquely identifying the row which you need to be updated? :) Here's what you can do (top off my head, as I worked on ASP.NET WebForms a long time ago :) ): 0. Select and bind your ID column to your grid but make it invisible. 1. Use DataKeys[^] property of grid for setting the "ID" field. 2. While updating a row, retrieve the "ID" value for it using its DataKeys property (and possibly its index). 3. Use this value to pass in to your update query, i.e. the value for your "@ID" parameter.

You have just been Sharapova'd.

[Norris Chappell]

I was able to do #1. #2 - Now to get the DataKeys what is the Code behind to do that?

[Norris Chappell]

Hi, I'm getting Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index Here is my code?

protected void Button_Update(object sender, EventArgs e)

        {
          using(SqlCommand cmd = new SqlCommand())
         {

             foreach (GridViewRow row in gvKeyPersonnel.Rows)
             {
                
                 cmd.Connection = conn;
                 conn.Open();
                 cmd.CommandText = "UPDATE SP2010\_EDCStaffing\_AppDB.dbo.CMS\_Key\_Personnel  SET  Name = @Name  WHERE ID = @id";

                     cmd.Parameters.AddWithValue("@id", Convert.ToInt32(gvKeyPersonnel.DataKeys\[row.RowIndex\].Values\[0\]));
                 cmd.Parameters.AddWithValue("@Name", Convert.ToString(gvKeyPersonnel.DataKeys\[row.RowIndex\].Values\[1\]));       

                 int numRegs = cmd.ExecuteNonQuery();
             }
               conn.Close();
         }
         }

Update the two Parameters but still gets the OOR error.

[Mycroft Holmes]

Your issue is probably on cmd.ExecuteNonQuery not returning anything from the query remove the int numregs = and see what you get

Never underestimate the power of human stupidity RAH

[Norris Chappell]

Mycroft, I am now getting Index was out of range. Must be non-negative and less than the size of the collection. Parameter name: index. I think something is wrong with this parameter? cmd.Parameters.AddWithValue("@Name", Convert.ToChar(gvKeyPersonnel.DataKeys[row.RowIndex].Values[0])); I don't know if I should have two Datakeys?

[Mycroft Holmes]

What I would do is create 2 variables to hold the cell values, put a break point in the loop and check the values before they are passed to the parameters.

Never underestimate the power of human stupidity RAH

[Agent__007]

Norris Chappell wrote:

cmd.Parameters.AddWithValue("@Name", Convert.ToString(gvKeyPersonnel.DataKeys[row.RowIndex].Values[1]));

This statement shouldn't be there, you should only have your "ID" field in the DataKeys. Instead, you should be having something like this:

cmd.Parameters.AddWithValue("@Name", row.Cells[IndexOfCellContainingNameField].Text); // Note that, I am assuming you are not having any template for your "Name" field, like a label, in which case you need to use FindControl() method on your cell and then use .Text on that label

Regarding the IndexOutOfRangeException you are getting, I think if you only have the "ID" in the DataKeys property (i.e. remove the "Name" from DataKeys and pass its value like the above line), that won't come up - assuming your RowIndex is not the culprit. Not related to your current question, but I think if you are having to iterate all rows in the grid for updating a row, you might want to have a look at examples here[^], here[^] or here[^].

You have just been Sharapova'd.

[Norris Chappell]

Hi, I don't have any of my fields with a label. I'm still getting an Out of Range error.

protected void Button_Update(object sender, EventArgs e)
{
using (SqlCommand cmd = new SqlCommand())
{

            // SqlDataReader myReader = null;
            // myReader = cmd.ExecuteReader();
            foreach (GridViewRow row in gvKeyPersonnel.Rows)
            {

                cmd.Connection = conn;
                conn.Open();

                cmd.CommandText = "UPDATE SP2010\_EDCStaffing\_AppDB.dbo.CMS\_Key\_Personnel  SET  Name = @Name, VDCIDIQ = @VDCIDIQ, VDCFFS = @VDCFFS, VDCHIM = @VDCHIM, VDCWEBHOSTING = @VDCWEBHOSTING, VDCCWF = @VDCCWF WHERE ID = @id";

                cmd.Parameters.AddWithValue("@id", Convert.ToInt32(gvKeyPersonnel.DataKeys\[row.RowIndex\].Values\[0\]));
                cmd.Parameters.AddWithValue("@Name", row.Cells\[1\].Text);
                cmd.Parameters.AddWithValue("@VDCIDIQ", row.Cells\[2\].Text);
                cmd.Parameters.AddWithValue("@VDCFFS", row.Cells\[3\].Text);
                cmd.Parameters.AddWithValue("@VDCHIM", row.Cells\[4\].Text);
                cmd.Parameters.AddWithValue("@VDCWEBHOSTING", row.Cells\[5\].Text);
                cmd.Parameters.AddWithValue("@VDCCWF", row.Cells\[6\].Text);
                cmd.ExecuteNonQuery();
            }
            conn.Close();
        }
    }

[Agent__007]

Just a quick suggestion - try your row.Cells[1].Text, row.Cells[2].Text, ... statements with [0], [1], and so on - i.e. with a Zero-based index. I think that should be it. If not, without a debugger, I can't help you any further, I am afraid.

You have just been Sharapova'd.

[Mycroft Holmes]

Caveat, can the user reorder your DGV columns, this would change the index of the cells and screw up your code.

Never underestimate the power of human stupidity RAH

[Pete OHanlon]

If you put a breakpoint on cmd.CommandText, press F5 and step through the code when the debugger hits this line. Look to see which one of those lines the application crashes on. As a hint, you can use Visual Studio to inspect the values of each cell to see what's in it.

[Norris Chappell]

Hi Pete, It crashes on this line: cmd.Parameters.AddWithValue("@id", Convert.ToInt32(gvKeyPersonnel.DataKeys[row.RowIndex].Values[0])); The value is null.

[Pete OHanlon]

Now that you know the line, you need to identify which part is the problem. Is it the DataKeys[row.RowIndex] or is it Values[0]? My suspicion is that it's the latter - in other words, you don't actually have a value in there.

[Norris Chappell]

I don't see the out of range error anymore. It doesn't update but deletes the first record in the database. I getting this error: The variable name '@id' has already been declared. Variable names must be unique within a query batch or stored procedure.

[Norris Chappell]

It appears I don't because I not getting that OOR error any more. I getting:The variable name '@id' has already been declared. Variable names must be unique within a query batch or stored procedure. Do I need to make any field Label instead of TextBox, The ID field is being is being hidden. I really don't know what is wrong now. Here is my present code. Maybe by looking at all of the code you might can spot something I missed. I have been working on this 4 straight days.

using System;
using System.Data;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.Sql;
using System.Data.SqlClient;
using System.Configuration;
using System.Web.UI.WebControls.WebParts;

namespace StaffingWebParts.KeyPerTest
{
public partial class KeyPerTestUserControl : UserControl
{
SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["SQLStaffingConn"].ConnectionString);
SqlCommand cmd = new SqlCommand();

    protected void Page\_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {
            DataTable dt = new DataTable();

            dt.Columns.Add("ID");
            dt.Columns.Add("Name");
            dt.Columns.Add("VDCIDIQ");
            dt.Columns.Add("VDCFFS");
            dt.Columns.Add("VDCHIM");
            dt.Columns.Add("VDCWEBHOSTING");
            dt.Columns.Add("VDCCWF");
            SqlDataReader myReader = null;
            SqlCommand cmd = new SqlCommand("SELECT ID, Name, VDCIDIQ , VDCFFS, VDCHIM, VDCWEBHOSTING, VDCCWF  from CMS\_Key\_Personnel where Name <> '   ' order by  Name");
            cmd.Connection = conn;
            conn.Open();
            myReader = cmd.ExecuteReader();
            while (myReader.Read())
            {
                DataRow dr = dt.NewRow();
                dr\[0\] = myReader\["ID"\].ToString();
                dr\[1\] = myReader\["Name"\].ToString();
                dr\[2\] = myReader\["VDCIDIQ"\].ToString();
                dr\[3\] = myReader\["VDCFFS"\].ToString();
                dr\[4\] = myReader\["VDCHIM"\].ToString();
                dr\[5\] = myReader\["VDCWEBHOSTING"\].ToString();
                dr\[6\] = myReader\["VDCCWF"\].ToString();
                dt.Rows.Add(dr);
            }
            
            gvKeyPersonnel.DataSource = dt;

[Pete OHanlon]

The reason you're getting this exception is because you're attempting to add the parameters to the same command object inside a loop. This will work on the first trip through the loop, but will fail on the next trip through. A way around this is to do cmd.Parameters.Clear(); before you start adding the parameters in. This will ensure the parameters collection has no entries on each journey through the loop.