Hello ASP.NET developers… Today I came across a small issue which killed a large amount of my development time. The issue was a little tricky between the lines of code. I have an ASP.NET gridview
which is dynamically (on the fly) created on my page. When I am inserting 2 lines of code just for allowing the gridview pagination, code breaks at runtime giving a NullReferenceException
.
Cause of the issue: I was adding the dynamically created gridview
(object) into page’s control collection after the databinding. This works fine if there is no pagination code added. But if there is code which allows pagination for the dynamically added gridview, this gridview should be added to the page’s control collection before the databinding.
Please see the below mentioned code blocks for the difference.
This piece of code will give the Null Reference Exception:
GridView gvDepartment = new GridView ();
gvDepartment.ID = "gvDepartment";
gvDepartment.AllowPaging = true;
gvDepartment.PageSize = 4;
gvDepartment.DataSource = GetDepartmentRows ();
gvDepartment.DataBind ();
this.form1.Controls.Add ( gvDepartment );
This is the perfect code:
GridView gvDepartment = new GridView ();
gvDepartment.ID = "gvDepartment";
gvDepartment.AllowPaging = true;
gvDepartment.PageSize = 4;
this.form1.Controls.Add ( gvDepartment );
gvDepartment.DataSource = GetDepartmentRows ();
gvDepartment.DataBind ();
I hope this post helped you or has given a nice thought. Thanks for reading. Please comment if you feel that there are any issues.
Please have a look into my blog for more posts: http://abinjaik.wordpress.com/.