gridview, how to build a image url in code behind?

I have a gridview control which contains an image field. However, the image url is built from several fields in my returned dataset. How do you concatenate those fields together, and at which point do I do 开发者_Python百科this so that I can pass that image url do my imagefield in my gridview? I am guessing it's on the RowDataBound but I don't know how to access each of the rows in my dataset?

Thanks.

I'm not sure what you are trying to concatenate without a code example, however I would perform the concatenation before binding the gridview and store it in a private member on the class so that you can access it later in the RowDataBound event.

You can use the row data bound event to find the control within that row and set its ImageUrl property.

private string m_ConcatUrl;

protected void gridView_RowDataBound(Object sender, GridViewRowEventArgs args)
{
    if(args.Row.RowType == DataControlRowType.DataRow)
    {
        Image imgCtrl = (Image) args.Row.FindControl("imgCtrl");
        imgCtrl.ImageUrl = m_ConcatUrl;
    }
}

You can use RowDataBound event to set the cell value.

void YourGridView_RowDataBound(Object sender, GridViewRowEventArgs e)
  {

    if(e.Row.RowType == DataControlRowType.DataRow)
    {
      // You can set your cell value in this
      e.Row.Cells[index] // use this to set the value in the cell 
    }

  }

In .NET 4, it would be like this:

if (e.Row.RowType == DataControlRowType.DataRow)  
{  
    string1 = e.Row.Cells[i].Text;
}

i is the index of the particular column you want to reference (e.g. Cells[0] is column 1).

I'm not sure if it's different in 3.5 but try that.