How to remove only one row among duplicate rows in a datatable - vb.net

Question

I've a datatable dtPackageTest with following rows in it
testid testname
------ -----------
1 abc
2 xyz
1 abc
2 xyz
I followed this answer to but it removes all the duplicate rows, and my expected output is
testid testname
------ -----------
1 abc
2 xyz
My code:
Dim tblDups = From r In dtPackageTest _
Group By Dups = New With {Key .testid = CInt(r("testid")), Key .test = CStr(r("test"))} Into Group _
Where (Group.Count > 1) _
Select Dups
Dim dupRowList = (From r In dtPackageTest _
Join dupRow In tblDups _
On dupRow.testid Equals CInt(r("testid")) _
And dupRow.test Equals CStr(r("test")) _
Select r).ToList()
For Each dup In dupRowList
dtPackageTest.Rows.Remove(dup)
Next

Answer 1

Make following changes in your existing code,this will work as you expected :
(I guess this should be an old school logic but it works )
'Add order by - Order By Dups.testid
Dim tblDups = From r In dtPackageTest _
Group By Dups = New With {Key .testid = CInt(r("testid")), Key .test = CStr(r("test"))} Into Group _
Where (Group.Count > 1) Order By Dups.testid _
Select Dups
'Add order by - Order By r("testid")
Dim dupRowList = (From r In dtPackageTest _
Join dupRow In tblDups _
On dupRow.testid Equals CInt(r("testid")) _
And dupRow.test Equals CStr(r("test")) Order By r("testid") _
Select r).ToList()
Dim id As Integer = 0
For Each dup In dupRowList
'Checking for testid is already removed or not
If id <> dup("testid") Then
id = dup("testid")
dtPackageTest.Rows.Remove(dup)
End If
Next