asp.net gridview head wrecker

samelterrance

Hi,

I have a gridview in asp.net.
I am looping through the gridview and where there is a particular value in the cell, I change the background color.

now what I want to do is where the value is 1, or a different color,
is to enable a hyperlink for those particular cells, not all of them.

here is my code, hope I make sense

Dim x As Integer
Dim y As Integer
For x = 0 To GridView1.Rows(0).Cells.Count - 1
If GridView1.Rows(0).Cells(x).Text = 1 Then
GridView1.Rows(0).Cells(x).BackColor = Drawing.Color.LightBlue
End If
For y = 0 To GridView1.Rows.Count - 1
If GridView1.Rows(y).Cells(x).Text = 1 Then
GridView1.Rows(y).Cells(x).BackColor = Drawing.Color.LightBlue
End If

Next



Next

Ginger

You could do it better using the RowCreated event to check each value and that way it will be rendered correctly. Or you could use the RowDataBound event

http://msdn2.microsoft.com/en-us/library/system.web.ui.webcontrols.gridview.rowcreated.aspx

http://msdn2.microsoft.com/en-us/library/system.web.ui.webcontrols.gridview.rowdatabound.aspx

Also http://msdn2.microsoft.com/en-us/library/system.web.ui.webcontrols.gridview.rowdatabound.aspx

samelterrance

Sorry, very new to this ginger.
I can't see from those articles how I can loops through each cell within the datagrid and how to dynamically make a cell a hyperlink based on it's value.

i.e 1st row, 1st column, value = 1, hyperlink ="boards.ie"
2nd row, 1st column, value = 0, no hyperlink

Evil Phil

What happens with the RowCreate and RowDataBound events is that when the row is created you have access to the cells and the data they are going to contain.

This means you won't have to loop though the entire GridView reading properties. You should also set the BackColor etc through css (I've commented out the code that does this below). Note the code below is untested so there's probably some minor flaws.

e.g.

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

		if(s.SomeValue == 1)
		{
			HyperLink hl = new HyperLink();
                        hl.Text = "Boards.ie";
                        hl.NavigateUrl = "http://www.boards.ie/";
                        e.Row.Cells[0].Controls.Add(hl);
			//e.Row.Cells[0].CssClass = "SomeCSSClassName";
			e.Row.Cells[0].BackColor = Drawing.Color.LightBlue;
		}

	}
}

samelterrance

Thanks Phil,

I think it's nearly there !!!!!! just some syntax issues as mine is awful.
I've converted most to vb.net accept for the first couple of lines below.

I still cant' see how this will check all cells in the gridview though.


Protected Sub GridView1_RowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
If e.Row.RowType = DataControlRowType.DataRow Then
SomeClassType s = (SomeClassType)e.Row.DataItem;
If s.SomeValue = 1 Then

Dim h1 As New HyperLink()
h1.Text = "boards.ie"
h1.NavigateUrl = "www.boards.ie"
e.Row.Cells(0).Controls.Add(h1)
e.Row.Cells(0).BackColor = Drawing.Color.LightBlue
End If
End If

End Sub

Evil Phil

If e.Row.RowType = DataControlRowType.DataRow Then
[b]Dim SomClassType s as SomeClassType
s = DirectCast(e.Row.DataItem, SomeClassType)[/b]
If s.SomeValue = 1 Then

I think is going to do it for you. You need to lookup casting in Vb.net.

What will happen is as each row in the grid view is created you can access that rows Cells collection, and work with each Cell in that Row.

samelterrance

I could kiss you now :-) kidding

I think I have it though, may not be coded the best but I think it does the job. what you think.


Dim x As Integer
x = 0

If e.Row.RowType = DataControlRowType.DataRow Then
For x = 0 To e.Row.Cells.Count - 1
If e.Row.Cells(x).Text = "1" Then
e.Row.Cells(x).Style.Add("background-color", "red")
Dim h1 As New HyperLink()
h1.Text = e.Row.Cells(x).Text
h1.NavigateUrl = "www.boards.ie"
e.Row.Cells(x).Controls.Add(h1)
End If
Next
End If

Evil Phil

Yeah that looks about right. Have a read of http://www.w3schools.com/css/default.asp for more details on CSS but your code is fine.

samelterrance

Thanks very much for all the help.

Evil Phil wrote:

Yeah that looks about right. Have a read of http://www.w3schools.com/css/default.asp for more details on CSS but your code is fine.

Ginger

If you read the MSDN for the base class you will see what the events are used for..

At least you have it working now. Remember you need to edit most of this stuff before the page is rendered otherwise it wont work