Cleaning up a nested for each-loop

[erik]

Hi. I'm comparing a temporary table to an another table, to check for changes in the cells. The way I'm doing it, is that I'm using three loops; one to loop trough the temporary, one to loop trough the other table and a last one to loop trough each column. Here's the code:

For Each row As DataRowView In View
                    For Each drow As DataRowView In view2
                        If row("emitid") = drow("emitid") Then
                            For Each column As DataColumn In View.Table.Columns
                                If Not row(column.ToString) = drow(column.ToString) Then
                                    row(column.ToString) = drow(column.ToString)
                                End If
                            Next
                            Exit For
                        End If
                    Next
                Next

"emitid" is the column I use as a reference to be sure that I'm comparing the correct rows, and the column order will always be the same in both tables. Is this the best way of doing what I want? I feel it looks a bit complicated...

[weirddemon]

You could probably use a recursive loop instead. I wouldn't know exactly how it would be done, but you might be able to find something via Google.

[jmcilhinney]

Is 'emitid' the primary key? Will both tables have the same values in that column?

[erik]

Is 'emitid' the primary key? Will both tables have the same values in that column?

Yes and yes

[jmcilhinney]

Yes and yes

In that case there's no need to loop through the second table over and over. You simply loop through the first table and then use the PK to get the corresponding row in the second table. I wouldn't worry about looping through the columns either. Just take the data from one row and put it in the other. If they are the same you haven't lost anything but if they're different you're covered.

For Each row1 As DataRow In table1.Rows
    Dim row2 As DataRow = table2.Rows.Find(row1("emitid"))
 
    row1.ItemArray = row2.ItemArray
Next