ProcessDataSet

#ProcessDataSet()

##Usage

The ProcessDataSet method is useful when you want to use post-processing in your application. This method should be overridden in your global.asax file.

public class CustomAdHocConfig : DatabaseAdHocConfig
{
	public override void ProcessDataSet(DataSet ds, string reportPart)
	{
		// Put your code here
	}
}

The first parameter is the System.Data.DataSet retrieved from the database. It is called "ds" here, but it can be named anything as long as the datatype remains the same. The second parameter is the name of the report in the ReportSet. For example, if part of your report is a grid named "Detail" and part of your report is a pie chart named "Chart", you can reference the grid part of your report by checking if ReportPart = "Detail". With that part of the report captured, you can manipulate it how you want and display the results.

In addition to manipulating the way your data looks, post-processing can assist with encryption, logging, localization, etc. The ProcessDataSet method will be called after your data has been retrieved from the database, but before it is displayed. This means you can manipulate the data however you want in order to display it as you want. For example, you can replace encrypted data values with decrypted ones. Let's explore post-processing with the ProcessDataSet method further.

##Example: Using post-processing

For example, we want to rename the "CA" region code to "California", but only in the results grid. Without any post-processing we have the following report:

Now let's add some extra code to the CustomAdHocConfig class:

public override void ProcessDataSet(DataSet ds, string reportPart)
{
    // We want to alter only "Detail" part of the report set
    if (reportPart == "Detail")
    {
        if (ds != null && ds.Tables.Count > 0 && ds.Tables[0] != null && ds.Tables[0].Rows.Count > 0)
        {
            // Iterate through columns to find column with name "Ship Region"
            for (int index = 0; index < ds.Tables[0].Columns.Count; index++)
            {
                if (ds.Tables[0].Columns[index].ColumnName == "Ship Region")
                {
                    foreach (DataRow row in ds.Tables[0].Rows)
                    {
                        if (row[index].ToString() == "CA")
                        row[index] = "California";
                    }
                    // There can be only one column with a specific name,
                    // so we can leave the cycle as soon as we find it
                    break;                                        
                }
            }
        }
    }
}

Public Overrides Sub ProcessDataSet(ByVal ds As DataSet, ByVal reportPart As String)
    'We want to alter only "Detail" part of the report set
    If reportPart = "Detail" Then
        If ds IsNot Nothing AndAlso ds.Tables.Count > 0 AndAlso ds.Tables(0) IsNot Nothing AndAlso ds.Tables(0).Rows.Count > 0 Then
	    'Iterate through columns to find column with name "Ship Region"
	    For index As Integer = 0 to ds.Tables(0).Columns.Count - 1
	        If ds.Tables(0).Columns(index).ColumnName = "Ship Region" Then
                    For Each row As DataRow In ds.Tables(0).Rows
		        If row(index).ToString() = "CA" Then
			    row(index) = "California"
			    'There can be only one column with a specific name,
			    'so we can leave the cycle as soon as we find it
			    break;
		        End If
                    Next
	        End If
	    Next
        End If
    End If
End Sub

And after implementing post-prosessor the result will be:

As you can see, "CA" was replaced by "California" in the grid but the chart still displays "CA". Using this approach, you can change data retrieved from the database in many ways.