changing column header text?

rmanapul · August 16th, 2012, 09:48 PM

Hi, i was so grateful to learn new things like LINQ to Entity and i use it a lot and incorporate it on my programming practice.

My problem is how can i change the column header text programmatically? when i use LINQ to Entity, the text in the column header appears as "Item" i tried different ways but all of them only resulted in error. can i change the column header text without using datasource controls, only with LINQ to ENTITY? thanks.

Imar · August 17th, 2012, 01:51 PM

Hi there,

You can set them up in markup, just as you could do when using a Data Source control.

To do it at run-time, you can access a property like Columns to change the name. You didn't mention which data control you're using, but if you were using a GridView you could do something like this:

Code:

GridView1.Columns[0].HeaderText = "Some new header";

Hope this helps,

Imar

rmanapul · August 21st, 2012, 08:13 PM

oh sorry i forgot to mention the name but yes, it's gridview im using. you will have to change it in the markup and not in the code-behind?

Imar · August 22nd, 2012, 03:21 AM

Hi there,

Quote:

you will have to change it in the markup and not in the code-behind?

I am not sure I understand this. Didn't my post mention both?

Imar

rmanapul · August 22nd, 2012, 03:33 AM

i tried to do it in the code behind but when i code it the .HeaderText property does not appear and it results to error. do i have to import anything before i use it? im using VB as my language

Imar · August 22nd, 2012, 03:42 AM

I guess that's near impossible to say without seeing the source code and the exact error message.

Cheers,

Imar

rmanapul · August 23rd, 2012, 08:48 PM

here is the complete code of the program:

Code:

Imports AlumniTblModel
Partial Class Management_Sample
    Inherits System.Web.UI.Page

    Protected Sub Page_Load(sender As Object, e As System.EventArgs) Handles Me.Load
        Using myEntities As New AlumniTblEntities

            Dim allProvinces = From province In myEntities.ProvinceTbls
                               Order By province.Province
                               Select province.Province




            ProvinceGrid.DataSource = allProvinces
            ProvinceGrid.DataBind()
            ProvinceGrid.Columns[0].HeaderText = "Provinces"

        End Using
    End Sub
End Class

when i typed the HeaderText, the intellisense does not show. and the Text "Provinces" does not appear as red color it's supposed to appear as red colored i think? can you also help me how to do paginating and sorting (when the header title is clicked) in this gridview programmatically? where you can only show 5 or 10 items per page.

Imar · August 24th, 2012, 02:28 AM

Hi there,

The example I posted was C#. Since you're using VB, you need parenthesis instead of brackets:

Code:

ProvinceGrid.Columns(0).HeaderText = "Provinces"

For paging, look at Skip and Take. However, in this case, since you're doing straight forward LINQ queries, I would suggest the EntityDataSource instead as it'll take care off all of this.

Cheers,

Imar

rmanapul · August 24th, 2012, 03:25 AM

When i tried to run the application, visual studio provided me with this message:

"Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index"

do i need to import something???

Imar · August 24th, 2012, 03:41 AM

Are you using auto generated columns? If so, they are not added the Columns collection which will remain at zero, causing this error. You can do it like this instead:

Code:

ProvinceGrid.HeaderRow.Cells(0).Text = "Provinces"

May I ask what you're trying to accomplish? Is there any reason why you're not explicitly defining the columns in the GridView and instead rely on run-time discovery? Also any reason for not using the EntityDataSource to handle binding, paging and sorting for you?

Imar