Loop through the rows of a particular DataTable

For Each row As DataRow In dtDataTable.Rows
    strDetail = row.Item("Detail")
Next row

There's also a shorthand:

For Each row As DataRow In dtDataTable.Rows
    strDetail = row("Detail")
Next row

Note that Microsoft's style guidelines for .Net now specifically recommend against using hungarian type prefixes for variables. Instead of "strDetail", for example, you should just use "Detail".

Dim row As DataRow
For Each row In dtDataTable.Rows
    Dim strDetail As String
    strDetail = row("Detail")
    Console.WriteLine("Processing Detail {0}", strDetail)
Next row