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Gridview update a column using another column

I have a gridview bound with a database. I would like to add an extra column which has a linkbutton. The intention is that when clicked on the linkbutton, the user could toggle the value of a column which is bounded with the database.
I don't have any good ideas how to get started on this. Any help would be greatly appreciated!
Regards, Thijs

If I understand you question,
Make you gridview template fields. you can find more about Using TemplateFields in the GridView Control
Place the linkbutton with a commandname. See ButtonField.CommandName Property
In here do the same for the field you need to access. You will be able to access the values and change as you need.
Hope this helps

Right the way I would approach this is declare a class called GridRecord or something that represents a grid row.
class GridRecord
{
}
then in the class define all properties that will be the columns of your grid including the link column.
class GridRecord
{
private Image m_Link = [some image];
public GridRecord(){}
public Image Link
{
get { return m_Link; }
}
}
then in your grid code:
IList<GridRecord> records = new List<GridRecords>();
//Fill records object as you like.
Grid1.DataSource = records;
Then handle the RowCellClick or similar event and check if the clicked cell is of property type Link and use it.

ASP.NET GridView Can't hide Columns

So I have an <asp:Gridview> and in my C# file, I am setting the datasource to some database table, and doing .DataBind().
However, I want to hide a column in the table based on a Boolean variable.
Something like this:
gridview.Columns['Field5'].Visible = false;
Or perhaps:
int c = gridview.Rows.Count();
for(int i = 0; i < c; i++){
gridview.Rows['Field5'].Remove();
}
Perhaps I cannot make it invisible, but I'm sure I can at least loop through and remove all rows related to the column "field5". I don't know how to go about doing this.
Does anyone perhaps have a proper link to using the GridView Class and how all the methods are suppose to be used because it's not clear, perhaps not written by microsoft?
Sorry if this is simplistic, the internet seems to lack a lot of C# documentation (or maybe it's just cluttered with too much useless ASP.net information).

No problem, the trick is that you have to reference the column by its index, not its name.
grid.Columns[1].Visible = false;

In your case you should loop through gridview and set cells you want to hide Visible=false
foreach (GridViewRow gvr in gv.Rows)
{
//here specify cell you want to hide
//also you may put any conditions
gvr.Cells[0].Visible = false; // Hide cell
}
To hide column you should go like that:
//here specify column you want to hide
grv.Columns[0].Visible = false; // Hide column
Also check this article http://www.codeproject.com/KB/webforms/Datagrid_Col_Example.aspx

I found a good method for doing something like that.
((DataControlField)gridView.Columns
.Cast<DataControlField>()
.Where(fld => (fld.HeaderText == "Title"))
.SingleOrDefault()).Visible = false;
I found it in below link
GridView Hide Column by code

The gridview is fine if you just want to quickly display some data, but don't need to modify it in any way. However if you do want to customize it, it is unpractical. It is easier and faster to build the table dynamically in your codebehind and you get all of the control you need.
Check out the first answer to this post: How to show pop up menu from database in gridview on each gridview row items?

Accessing properties of SelectedRow during SelectedIndexChanged event in dynamically generated GridView

I have an empty GridView object on a page that I bind to a LINQ qry result at run time. The GridView has a 'Select" button that fires the SelectedIndexChanged event and it's inside of this event that I'd like to access the data of one of the fields in the selected row.
So far, I can only find one way to do this, and it seems suboptimal:
protected void GridView2_SelectedIndexChanged(object sender, EventArgs e)
{
GridViewRow row = GridView2.SelectedRow;
string UserID = row.Cells[1].Text;
//Do stuff with the userID
}
So this just access the cell data directly based on the cell index. The UserID just happens to be in the second cell and so it works. But later down the road, the UserID may not be in that same column. It seems like I'd be better off looking up the value of this cell by accessing by the cell's header name, or by any method other than the cell index itself.
Any ideas?
Thanks!

Try this
User user = (User)((DataRowView)row.DataBoundItem).Row;
int userID = user.UserID;
I am assuming you have a class called User and you are binding the DataGridView to may a List

I don't know much about asp.net, but in the C# DataGridView you can index columns directly by column name, i.e.
string UserID = row.Cells["UserID"].Text;
or something like that. Might be worth a try.

You can use following code to retrieve object bound to current SelectedRow.
DataTable dt = (DataTable)<GridViewControl>.SelectedRow.DataItem
(here I have assumed that Grid is bound with DataTable.)

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.

Set boundcolumn width in gridview isn't working

I have a report page that can display two different reports. So I have a GridView with no columns on my aspx page. I am adding 4 BoundFields to the GridView in the button click event handler. The first column is the one I need to set the width of for one of the reports (the code I'm using to add this column is below).
gvReport.Columns.Clear();
BoundField bf1 = new BoundField();
...
if (ddReportType.SelectedValue == "full") {
bf1.HeaderText = "Facility";
bf1.DataField = "Facility";
bf1.ItemStyle.Wrap = true;
bf1.ItemStyle.Width = 150;
bf1.Visible = true;
gvReport.Columns.Add(bf1);
...
The problem is there is one row that has a SHA512 hash in this column. Since there is no space in the middle of it, the gridview won't wrap it (I think that's what is happening, anyway)! So I thought I'd catch this column in the OnRowDataBound event and add a space in the middle of the hash so it will wrap, but I can't figure out how to reference the BoundField. There's no ID property. Does anyone have a suggestion? Either on how to reference the BoundField, or another way to get this to display nicely?
I had the columns in the aspx file originally and tried using:
gvReport.Columns[0].ItemStyle.Width = 150;
gvReport.Columns[0].ItemStyle.Wrap = true;
but that didn't work either. This is very frustrating!

So we went with Plan C. I never did figure out how to reference the BoundField. We got around that problem by creating two GridViews in the markup and just changing which one is visible. To solve the problem of the text that won't wrap, we're catching it in the OnRowDataBound event handler and checking the length of the text. We just insert a space in the middle, and voila! It wraps!

The BoundField is a wrong thing. It is more like a definition. Later, when binding or creating rows, you are dealing with rows, cells, and data items.
You could do something like this:
protected void grid_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowType == DataControlRowType.DataRow)
{
string value = e.Row.Cells[1].Text;
if (!string.IsNullOrEmpty(value))
e.Row.Cells[1].Text = value.Insert(value.Length / 2, " ");
}
}
where Cell[1] is the column containing long values. In the same place, you could use e.Row.DataItem to get actual data, but then you'd need to know its type.
You could create a template field and bind to an expression or use its child's data bound event to do the same.
Also, if you were using a DataSet, you could set up calculated field and bind to it. Anyway...