[RESOLVED] Gridview Paging

[jlbantang]

I have a web application which does data filtering. The return data set will be bind to Datagridview with Paging set to True.

Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        Using connection As New SqlConnection("Data Source=localhost\sqlexpress;Initial Catalog=26may;Integrated Security=SSPI;")
            Dim criteria As String = String.Empty
            Dim sql As String = "SELECT pk_ddlvryMasterid,pk_ddlvryno as [Dlvry No],convert(varchar,entereddate,106) as Dated" & _
                    ", lpono as LPO_No, Supplier FROM qDDlvryMaster"
 
            Select Case criteriaDropDownList.Text.ToUpper
                Case "DLVRY NO" : criteria = "PK_DDLVRYNO"
                Case "LPO NO" : criteria = "LPONO"
                Case "SUPPLIER" : criteria = "SUPPLIER"
            End Select
            
            Using command As New SqlCommand(sql & " where " & criteria & " LIKE @value + '%'", connection)
                command.Parameters.Add("@value", Data.SqlDbType.VarChar).Value = valueTextBox.Text.ToString
 
                connection.Open()
                Using reader As SqlDataReader = command.ExecuteReader()
                    Dim tb As New DataTable
                    tb.Load(reader)
                    GridView1.DataSource = tb 'set datasource
                    GridView1.DataBind() 'bind to gridview to view return data set
                End Using
 
 
            End Using
        End Using
 
    End Sub
 
 
    Protected Sub OnPaging(ByVal sender As Object, ByVal e As GridViewPageEventArgs) Handles GridView1.PageIndexChanging
 
        GridView1.PageIndex = e.NewPageIndex
        GridView1.DataBind()
 
    End Sub

The code works perfectly but every time I move to different page the gridview clear all the rows.

And also how can I make the first gridview column create link to its details page?

[HowTo]

The code works perfectly but every time I move to different page the gridview clear all the rows.

'do this in page load event
if not Me.IsPostBack then
'bind the gridview
end if

And also how can I make the first gridview column create link to its details page?

withing the <itemTemplate> take a linkbutton and then you can easily access the link button

[jlbantang]

hey,

I added like this:

If Me.IsPostBack Then
            Call Button1_Click(sender, e) 'call button to fillin datagrid
        End If

Also I added the linkbutton inside the Grid ItemTemplate but it did not do anything when the page re-run.

I want to pass the column pk_ddlvryMasterid value to the details page. Im trying to look at ASP.NET website for some tutorial similar to this regard but I cant find one. Do you any graphical/video tutorial similar to this thread?

BTW columns are not defined in gridview.

Thanks.

[avrail]

hay,

have a look
http://msdn.microsoft.com/en-us/library/ms972948.aspx
http://www.codeproject.com/KB/webfor..._GridView.aspx

you can use the Item templates to add any thing to your GridView.
and also, your grid didn't show any thing after paging because your Grid must have its Datasource after the reload,

    Protected Sub OnPaging(ByVal sender As Object, ByVal e As GridViewPageEventArgs) Handles GridView1.PageIndexChanging
 
        GridView1.PageIndex = e.NewPageIndex
        GridView1.DataBind()
    End Sub

in this code you didn't give your GridView the Datasource

[avrail]

i believe that the HOWTo will work also

[HowTo]

hey,

If Me.IsPostBack Then
            Call Button1_Click(sender, e) 'call button to fillin datagrid
        End If

try to avoid this code;i want to tell that create a function and then call that function from where ever you want.........e.g;from the button click,page load,etc etc

[gep13]

And also how can I make the first gridview column create link to its details page?

Have a look here:

http://www.asp.net/data-access/tutor...-detailview-cs

Gary

[jlbantang]

try to avoid this code;i want to tell that create a function and then call that function from where ever you want.........e.g;from the button click,page load,etc etc

Can you please tell me why should I avoid the code when the function Im going to create will perform the same task.

[avrail]

hay,
there is no harm from doing this, i believe he means you can use these lines of codes in any place you want.

do you still have problems ??

[gep13]

What HowTo is referring to, is that you shouldn't directly call the click event of a button.

If you need to repeat the code that is executed in a button, move that code into it's own method. Then call this method from button the click event, and also in other places that you need it.

Does that make sense?

Gary

[jlbantang]

hey,

Yes indeed . If I am correct you just mention what he say and did not reason out the difference. I am thinking of someone answer the WHY SHOULD WE DO THAT?

[gep13]

The reason is quite simply it is bad practice.

When you call the click event directly, you don't actually know the value of sender and e, these are normally created for you, when the click event is invoked. However, in calling it directly, you either need to create these properties, which you can't really do, or set them equal to null.

In Windows Form world, there is the PerformClick method on a button, which can be used to perform the action of clicking the button, but this does not exist in the world of ASP.Net.

Gary

[HowTo]

The reason is quite simply it is bad practice.

When you call the click event directly, you don't actually know the value of sender and e, these are normally created for you, when the click event is invoked. However, in calling it directly, you either need to create these properties, which you can't really do, or set them equal to null.

In Windows Form world, there is the PerformClick method on a button, which can be used to perform the action of clicking the button, but this does not exist in the world of ASP.Net.

Gary

thats exactly what i tried to mean but i was a bit late on this thread to explain him why should not we do that

thanks Gary

[gep13]

thats exactly what i tried to mean but i was a bit late on this thread to explain him why should not we do that

thanks Gary

No probs.

[jlbantang]

It mean a lotta things.

thanks.

[gep13]

Hey,

I am glad to hear that you got this sorted out.

Out of interest, what was the solution to your problem? It will help other people in the community.

Gary