asked on

Paging in GridView

When click on the second page of a gridview I get the following error;

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

error line;

Line 213: string Assignid = ((Label)(GridView1.Rows[rowIndex].FindControl("lblAssignId"))).Text.ToString();

the error is generated from this line of markup

<asp:TemplateField ShowHeader="False" meta:resourcekey="TemplateFieldResource5">
<ItemTemplate>
<asp:LinkButton ID="lbA" runat="server" CausesValidation="False" CommandName="Ap" CommandArgument='<%# Container.DisplayIndex %>' Text="Approve" meta:resourcekey="lbApproveResource1"></asp:LinkButton>
</ItemTemplate>
</asp:TemplateField>

code-behind

protected void ItemCommand(object sender, GridViewCommandEventArgs e)

{
int rowIndex = Convert.ToInt32(e.CommandArgument);

string Assignid = ((Label)(GridView1.Rows[rowIndex].FindControl("lblAssignId"))).Text.ToString();
pls help me tofix the error.

thanks

ayha

AndyAinscow

int rowIndex = Convert.ToInt32(e.CommandArgument);

And what is the value of rowIndex ?

ayha1999

ASKER

rowIndex value is value of "Container.DisplayIndex": from the following field

<asp:LinkButton ID="lbA" runat="server" CausesValidation="False" CommandName="Ap" CommandArgument='<%# Container.DisplayIndex %>' Text="Approve" meta:resourcekey="lbApproveResource1"></asp:LinkButton>

AndyAinscow

But what is the value 2, -37, 987657....

ayha1999

ASKER

did I mentioned 2, -37, 987657.... anywhere in my question? only two rows there in my gridview. when click on the 2nd page the error occurs.

AndyAinscow

From your question
Index was out of range. Must be non-negative and less than the size of the collection.

I am asking you, now for the third time, what is the value of the index. Believe me it should help in solving your problem.

ayha1999

ASKER

value of rowIndex is 2.

AndyAinscow

OK, how many rows do you have in your gridview?

ayha1999

ASKER

only two rows.

AndyAinscow

That is your problem.
The first row has an index of 0, the second has an index of 1.

ayha1999

ASKER

yes. how can I fix it?

AndyAinscow

The obvious fix is
int rowIndex = Convert.ToInt32(e.CommandArgument) - 1;

but I don't know if you actually send a zero for the first row. It all depends on what you use for the e.CommandArgument

ayha1999

ASKER

the purpose of the rowIndex is:

protected void ItemCommand(object sender, GridViewCommandEventArgs e)
{
int rowIndex = Convert.ToInt32(e.CommandArgument);

string RequestId = ((Label)(GridView1.Rows[rowIndex].FindControl("lblRequestId"))).Text;
if (User.IsInRole("Admin"))
{
Response.Redirect("~/PassEntry.aspx?RequestId=" + RequestId.ToString());
}
else

AndyAinscow

I don't see your complete code, I don't know what it should be doing.

I have helped you find the error and told you why you get the error. Exactly what you do is really up to your requirements.

IF the index is always 1 too many then just subtract 1.
If the index is usually correct then you need to check if the index is greater than the number of rows (or less than zero) and take appropriate action (leave the function / give a warning / ....)

ayha1999

ASKER

even , int rowIndex = Convert.ToInt32(e.CommandArgument) - 1; give me the same error.

AndyAinscow

What is the value of rowIndex when that gives the error ?

ayha1999

ASKER

rowIndex=1

AndyAinscow

OK.
This is what you say
GridView1.Rows[1] gives you an 'Index out of range' error, and GridView1 has 2 rows at that point.

That makes me think that GridView1 isn't what you think it is.

Have some code like this AND CHECK THE VALUES

int rowIndex = Convert.ToInt32(e.CommandArgument) - 1;
int rowCount = GridView1.Rows.Count;

ayha1999

ASKER

rowIndex = 1
rowCount = 1

AndyAinscow

rowCount = 1 means (as I told you earlier) that the only valid index is 0. Hence the error.

ayha1999

ASKER

so what is the solution here? I think by changing the following lines it can be solved.

int rowIndex = Convert.ToInt32(e.CommandArgument);

string RequestId = ((Label)(GridView1.Rows[rowIndex].FindControl("lblRequestId"))).Text;

I want to retrive the value of lblRequestId Label in the item command. that's what I am doing here. is there any other way I can retrive the value?

but I have no idea how to do it.

AndyAinscow

I don't know where this e.CommandArgument comes from.
I also don't know if this function is being called multiple times, sometimes with the value you expect and then with an out of range value.

You should know these things AND, more importantly, what you need to do in those cases.

I **guess** you have always a value 1 more than the actual row index.

ayha1999

ASKER

e.CommandArugment comes from;

<asp:LinkButton ID="lbA" runat="server" CausesValidation="False" CommandName="Ap" CommandArgument='<%# Container.DisplayIndex %>' Text="Approve" meta:resourcekey="lbApproveResource1"></asp:LinkButton>

I have linkbuttons in the gridvew1. when user click on any link button, I want to retrieve the value of the clicked row. (value of any cell(0) for example.) to find the clicked row I use the above e.CommandArugment.

is there any other way to get the value? I think that will solve the paging problem.

thanks

ASKER CERTIFIED SOLUTION

AndyAinscow

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ayha1999

ASKER

without deducting it the problem is solved.

if (e.CommandName == "CreateWo")
{
int rowIndex = Convert.ToInt32(e.CommandArgument);
string RequestId = ((Label)(GridView1.Rows[rowIndex].FindControl("lblRequestId"))).Text;
}
else if (e.CommandName == "Approve") <----- only 'else' was here. I changed to 'else if'
{
int rowIndex = Convert.ToInt32(e.CommandArgument);
// int rowCount = GridView1.Rows.Count;

thank u very much for your time and support