Tuesday, April 8, 2008

ObjectDataSource : Manually controlling the sorting expression.

By default the GenWise ASP.NET Templates uses the object datasource SortParamterName. When that property is used , the objectdatasource will manipulate internally the sort expression (change to asc , desc) .

  269     ObjectDataSource runat="server" ID="ObjectDataSource1" TypeName="BOLayer.CustomerFactory"
  270                 SelectCountMethod="Count" EnablePaging="True" UpdateMethod="Save" DeleteMethod="Delete"
  271                 SortParameterName="pSortExpression" MaximumRowsParameterName="pMaxResult" StartRowIndexParameterName="pFirstResult"
  272                 SelectMethod="GetAll">
  273                 
  274                     Parameter Name="pSortExpression">Parameter>
  275                     Parameter Name="pCriteria">Parameter>
  276                 
  277                 
  278                     Parameter Name="CustomerID">Parameter>
  279                 
  280             ObjectDataSource>


For more advanced sorting scenarios you might want to manually control what's passed to the pSortExpression method parameter. This can be done in the following way :

Subscribe to the ObjectDataSource Selecting method (genwise does that automatically)
   44 ObjectDataSource1.Selecting += new ObjectDataSourceSelectingEventHandler(ObjectDataSource1_Selecting);



  253    protected void ObjectDataSource1_Selecting(object pSender, ObjectDataSourceSelectingEventArgs pEventArgs)
  254         {
  255             if (pEventArgs.ExecutingSelectCount)
  256                 pEventArgs.InputParameters.Remove("pSortExpression");
  257             else
  258                 pEventArgs.InputParameters["pSortExpression"] = _newSortExpression;
  259 
  260             pEventArgs.InputParameters["pCriteria"] = Browse1_GetCriteria();
  261         }

Where does _newSortExpression come from ?


  198         string _newSortExpression = null;
  199         protected void Browse1_Sorting(object pSender, GridViewSortEventArgs pEventArgs)
  200         {
  201             // Calls this method to adapt the sort syntax (required for Composite sorting).
  202             _newSortExpression = WebUtils.SortExpressionTransformer(pEventArgs);
  203             pEventArgs.Cancel = true;
  204         }


SortExpression Tranformer takes the ObjectDataSource parameters and manipulates them to make them compatible with the GenWise Factories sorting syntax.

Below is the code of this method:

   63   public static string SortExpressionTransformer(GridViewSortEventArgs pEventArgs)
   64     {
   65         if (pEventArgs == null) throw new ArgumentNullException("pEventArgs");
   66 
   67         if (pEventArgs.SortDirection == SortDirection.Ascending)
   68         {
   69             return pEventArgs.SortExpression;
   70         }
   71 
   72         string newSortExpression = pEventArgs.SortExpression;
   73         string DESC = " DESC";
   74 
   75         if (pEventArgs.SortDirection == SortDirection.Descending)
   76         {
   77             if (pEventArgs.SortExpression.Contains(","))
   78             {
   79                 // Case : We have a composite sorting ( Field1,Field2) 
   80                 newSortExpression = string.Empty;
   81                 string[] sortParts = pEventArgs.SortExpression.Split(',');
   82                 for (int i = 0; i <> 
   83                 {
   84                     string sortPart = sortParts[i];
   85 
   86                     int sortDirectionIndex = sortPart.IndexOf(DESC);
   87                     bool isDescending = (sortDirectionIndex > -1);
   88 
   89                     string property = sortPart;
   90                     if (isDescending)
   91                     {
   92                         // sta : udpate templates.
   93                         //property = sortPart.Substring(0, (sortPart.Length - sortDirectionIndex + 1));
   94                         property = sortPart.Substring(0, (sortPart.Length - sortDirectionIndex + 1 + DESC.Length));
   95                     }
   96 
   97                     if (i > 0) newSortExpression += ",";
   98                     newSortExpression += property;
   99 
  100                     // Only add the DESC to all except the last (Last one will be controlled automatically by the object datasource.
  101                     if (!isDescending)
  102                     {
  103                         if (i < (sortParts.Length - 1))
  104                             newSortExpression +=  DESC ;
  105                     }
  106                 }
  107                 pEventArgs.SortExpression = newSortExpression;
  108             }
  109         }
  110         return newSortExpression;
  111     }

Monday, April 7, 2008

GenWise generated project added to vs.net solution using Source control.

Several customers have asked me how they can integrate an existing GenWise project into their vs.net solutions. To be more specific, GenWise already generates 100% compatible project files, so what's the problem?

Well, If you want to add the generated project into an existing solution and at the same time you can to keep that solution in source safe ( or in sourcegear vault which I use and recommend) then you might hit some little problems.

Problem #1 : Every time you regenerate the project is seen as a "new" project for the solution.
The reason behind this is that when you add the project to the solution the .proj file is modified with specific source control information + and ID (Guid) is given, etc.
To solve this problem you can "copy/paste" this information from the "modified" version of the project file INTO the GenWise project, so when you re-generate you don't loose this info .

Click on the image to enlarge an example for the solution to problem #1.




Problem #2 : After you have added the project to a source control provider ( vss or vault) all the files will be automatically read-only (by default) so you need to explicity do a complete project check out before you use the regenerate options from GenWise.