LoadMethodParameters lost when paging/sorting

Sierra · January 10th, 2010, 04:52 AM

With a customgridview using LoadMethodParameters, the gridview will load successfully the first time the page is loaded. But when using the paging or sorting links the following error occurs: System.MissingMethodException
...method not found.

This error does not happen for any method without parameters. It's as if these parameters are lost.

Here is the code:

Code:

if (!IsPostBack)
{
cgvKBArticles.ListClassName = typeof(KBArticleEOList).AssemblyQualifiedName;

cgvKBArticles.LoadMethodName = "LoadByTopic";
cgvKBArticles.LoadMethodParameters.Add(topicId);

cgvKBArticles.AddBoundField("", "Actions", "");
cgvKBArticles.AddBoundField("TopicName", "Topic", "TopicName");

cgvKBArticles.DataBind();
}

(topicId is an int from the querystring)

If I remove the IsPostBack if statement, the paging/sorting works on the above example but the gridview columns get duplicated.

I noticed that the methodparameters are not stored in viewstate in the CustomGridView class. Is this causing the problem or am I missing something else?

Thanks in advance.

ocn · January 17th, 2010, 12:37 AM

I have the same problem. Does anyone have a solution for it?

Thanks!

Sierra · January 18th, 2010, 05:27 PM

I've updated the CustomGridView class to save the methodParameters to viewstate. Now the paging and sorting works.

Code:

        public ArrayList LoadMethodParameters
        {
            get
            {
                if (ViewState["LoadMethodParameters"] == null)
                    return _methodParameters;
                else
                    return (ArrayList)ViewState["LoadMethodParameters"];
            }

            set { ViewState["LoadMethodParameters"] = value; }
        }

...

        private void BindGridView(string sortExpression, SortDirection sortDirection)
        {
            //Create an instance of the list object
            Type objectType = Type.GetType(ListClassName);
            object listObject = Activator.CreateInstance(objectType);

            //Call the method to load the object
            //objectType.InvokeMember(LoadMethodName, BindingFlags.InvokeMethod, null, listObject, new object[] { });
            objectType.InvokeMember(LoadMethodName, BindingFlags.InvokeMethod, null, listObject, LoadMethodParameters.ToArray());

            //Call the SortByPropertyName method.  This is in the ENTBaseBOList class.  The object must inherit
            //from this class.
            base.DataSource = objectType.InvokeMember("SortByPropertyName", BindingFlags.InvokeMethod, null, listObject, new object[] { sortExpression, sortDirection == SortDirection.Ascending });
            base.DataBind();

            //Save the sortExpression and sortDirection to the view state.
            SortExpressionLast = sortExpression;
            SortDirectionLast = sortDirection;
            LoadMethodParameters = LoadMethodParameters;

            objectType = null;
            listObject = null;
        }

Is there a more efficient way to do it or is this the best way?