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Updating a particular cell of a gridview is not working , the update is not occured and there are some issues

Good evening,someone asked me to help her with fixing some code for asp.net, she showed me her code but I couldn't find a way to fix it .So I'm wondering if someone would take his time to help me fixing it.
As she said , she's using asp.net ( net f.4 ) .On a page she added a gridview and used a sqldatasource to bind the information from data table to the gridview .
The aim is , on the GridView row_updating if the condition is true
then a certain cell of the current editing row will be updated with a
new value.
But , here is the problem :
Let's say I have two rows on the gridview!
If I click the edit button of the first row and then press the update button nothing happens.
But when I click the edit button of the second row then I can see the
updated value for the cell updated of the first row and If I click update or cancel I
can't see the value anymore.
And in the datatable the value is not updated.
Can someone help me fix it?
Thanks

Thats because you are not updating your gridview after executing Update statement. You need to call DataBind() after update on gridview
GridView1.DataSource = yourDataSource;
GridView1.DataBind();

You need to assign the ID to the DataKeyNames property, and then you can get the value like this:
<asp:GridView ID="GridView1" runat="server" DataKeyNames="ID" ...>
And in code-behind, you can get the ID like this:
var ID = (int)GridView1.DataKeys[e.RowIndex]["ID"];

Get the value of a column that is using a ButtonField

I have a GridView and one of the columns has a TemplateField using a LinkButton (ButtonField)
I can get the value of a specific cell in my Grid Just fine. Using:
GridViewRow row = GridView1.SelectedRow;
lblSalesmanCustomers.Text = row.Cells[2].Text;
I then display the text from that cell in a Label.
However I cannot get this to work with a ButtonField Template. It only works with a non Template column.
How can I get the value of a specific cell in a column that is using a ButtonField / TemplateField?
EDIT: This is My Button Field Code inside my GridView:
<asp:ButtonField DataTextField="Customer" HeaderText="Customer" ButtonType="Link" CommandName="Select" />
Also, this is happening in this event:
protected void gvManagerCustomers_SelectedIndexChanged(object sender, EventArgs e)

See if var Button = row.Cells["Customer"].Controls[0]; would retrieve the button you need.
You might need to cast it to the correct type.

I know there are issues with hyperlinkfield and buttonfield but there is a work around. Say you are binding buttonfield text based on a column called ButtonNames, and in that column you have all your names, such as "button bob", "button jerry" etc. In your GridView, add an invisible column as your very first column and bind its value as ButtonNames. You make it invisible by setting one of the visibility properties. Forgot what it was from top of my head. Then, when you want to get the text for the buttonfield simply get the data from that invisible column instead Same applies to hyperlinkfiends.
EDIT: here's some code.
<asp:BoundColumn ItemStyle-HorizontalAlign="Left" DataField="ButtonNames" SortExpression="ButtonNames" HeaderText="TriageId" Visible="false" ReadOnly="true"></asp:BoundColumn>
Then you retrieve it via string s = e.Item.Cells[0].Text where e is a DataGridCommandEventArgs or something to that nature.

There will be a controls collection in the cell - you may be able to access it there.
Though a simpler way would be to use something like:
Label l = row.FindControl("myControlId");
EDIT: true the exact approach above does not work - but you can use the controls, the following does work, note that what we are doing here is pretty much rife with bad practices (but then we are using a GridView for convenience sake after all).
protected void gvManagerCustomers_SelectedIndexChanged(object sender, EventArgs e)
{
var x = ((sender as GridView).SelectedRow.Cells[0].Controls[0] as LinkButton).Text;
}
In order to figure this out set up a debug environment and breakpoint in the handler method then drill down through the class hierarchy. The debugger is our friend ;)
EDIT just to mention the obvious - the column is hard coded here - you will probably have to change it.

Changing text of an autogenerated select column of a gridview in asp.net - How?

I would like to change the text of the autogenerated "select" column in an ASP.NET GridView control. The text needs to be changed to the value of a DataField.
I suspect that there is a very logical way to do this but I am missing it.
I am able to add controls and data via the pre-render event but is there an easier better way?

Use the TemplateField and place into it buttons or linkbuttons with appropriate CommandName property: ButtonField.CommandName Property
You may set this button text using DataBinder.Eval method.

The easiest way I found to do this is after the calling DataBind() just before the gridview control is displayed.
foreach (GridViewRow row in gvAgreementList.Rows)
{
LinkButton lb = (LinkButton) row.Cells[0].Controls[0];
lb.Text = "Edit";
}

after <column> write this:
<asp:CommandField ShowSelectButton="True" SelectText="Save" />
and remove AutoGenerateSelectButton="True" from Gridview attribute.

First remove auto generated select then go to GridView tasks.. top right Button of GridView and then click on commandfields -> Select then edit SelectText.
(Edited answer of ShaileshK with some changes)

Go to GridVIew tasks.. top right Button of GridView and then click on edit columns
In selected fields section Click on select field. change the value of select text.
done.

ASP.NET C# - Removing a column from a datalist

I have a datalist inside a usercontrol that gets loaded into a page where users can customize a report based on some checkboxes.
One of the checkboxes, however, is "Hide Worklog" which should hide the worklog column from the result set because it can be quite long and interfere with the report.
If I do:
datatable1.Columns.Remove("WorkLog");
the code throws an exception because:
<asp:Label ID="WorkLog" runat="server" Text='<%# Bind("WorkLog") %>'></asp:Label></td>
doesn't exist.
Am I going about the usercontrol all wrong? This usercontrol should always be able to show the worklog, so I don't think it's bad to bind it in there, but at the same time I want to be able to hide it if the user wants.

Try removing the label control from your DataList instead of removing the column from the data source (i.e. the DataTable)
DataList1.Controls.Remove(DataList1.FindControl("WorkLog"));
You shouldn't get an error if the data source has more columns than you're displaying on the page, however, you will get an error, as you've discovered, if you're trying to display a column that doesn't exist in the data source.

bind it in code behind after checking some condition. like
if (visible) {
//bind
}
while removing control
visible = false;
you might need to change visible to session var :)

C# Add HyperLinkColumn to GridView

I'm trying to add HyperLinkColumns dynamically to my GridView. I have the following code:
HyperLinkColumn objHC = new HyperLinkColumn();
objHC.DataNavigateUrlField = "title";
objHC.DataTextField = "Link text";
objHC.DataNavigateUrlFormatString = "id, title";
objHC.DataTextFormatString = "{2}";
GridView1.Columns.Add(objHC);
This doesn't work, so.. how can i add a HyperLinkColumn to my GridView?

You might want to add it when the row is binded:
protected void yourGrid_RowDataBound(object sender, GridViewRowEventArgs e)
{
HyperLink hlControl = new HyperLink();
hlControl.Text = e.Row.Cells[2].Text; //Take back the text (let say you want it in cell of index 2)
hlControl.NavigateUrl = "http://www.stackoverflow.com";
e.Row.Cells[2].Controls.Add(hlControl);//index 2 for the example
}

You have to do it before the DataBinding takes place, check the GridView Events.

I think you should be using a HyperLinkField not a HyperLinkColumn.

In case, if you just want to redirect to another URL then simple use HyperLink web control and push it in the desired cell of GridView Row at RowDataBound event.
OR
If you want to perform any server event before sending it to another URL, try this
1) Add LinkButton object at RowDataBound event of GridView.
2) Set the CommandName, CommandArgument property, if requried to pass any data to this object.
3) Capture this event by handling the RowCommand event of the GridView.

By the way, I just think that you can use the DataGridView and in the Designer select the Link column and your problem would be over. The DataGridView does have a link column, than you just need to add an event on "Click" and you will be able to have what you want. This solution works if you can switch to DataGridView.

I know this thread is old but couldn't help adding my 2 cents. The procedure explained in the following tutorial worked perfectly for me:
ASP Alliance

It seems you have got things mixed up. I don't know - how that code compiles?
GridView's column collection can accept columns of type "DataControlField".
I think you need to initialize HyperLinkField and set relevant properties (text, NavigateUrl, HeaderText, Target) and add it to the columns collection.
HyperLinkColumn class is meaningful when you are using DataGrid (not in case of GridView).
Hope that helps.