Removing a row from a datatable - vb.net

Question

I have a program that asks the user a series of questions that are collected from a database and stored in a datatable.
I have a system that chooses two random numbers, one to determine which question and one to determine what order the answers are displayed. I want questions to remain in the datatable until the user gets it correct, and afterwards that question cannot come up again.
My datatable is called DT, and there's a line of code:
DT.Rows.RemoveAt(QNumber)
Which sounds like it should remove the row selected. However I have a question regarding this.
If for example QNumber was 2, and so row 2 was deleted. Would this then move everything from row 3 in to row 2, and then everything from row 4 to row 3 and so on, or would this just make row 2 blank, and so break my code?

Answer 1

Since you didn't post any context are some test snippets:
Button1_Click loads a table
Button2_Click "processes" each row and optionally deletes the row.
In your case "process" would mean: display the question and loop until you get an answer.
In your case Button2 code would determine which record to load, probably using .Select() on the datatable that returns the "question" to ask, and eventually delete.
Dim da As SqlDataAdapter
Dim ds As DataSet
Dim dt As DataTable
Dim con As New System.Data.SqlClient.SqlConnection()
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
Try
Using con As New System.Data.SqlClient.SqlConnection()
con.ConnectionString = "Data Source=APCD03;Initial Catalog=OIStest;Integrated Security=True"
Dim rdr As Data.SqlClient.SqlDataReader
con.Open()
Dim cmd As New SqlCommand("SELECT [DBLinked] as PK ,[TEBackupDate] FROM [OISTest].[dbo].[_DBLink]", con)
rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection)
dt = New DataTable
dt.Load(rdr)
rdr.Close()
End Using
Catch ex As Exception
MsgBox(ex, ex.Message)
End Try
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
For Each row As DataRow In dt.Rows
If Not row.RowState = DataRowState.Deleted Then
If MsgBox("Delete this row, PK: " & row("PK"), vbYesNo) = MsgBoxResult.Yes Then
row.Delete()
End If
End If
Next
End Sub
Button3 demos selecting a specific row to process and delete:
Private Sub Button3_Click(sender As Object, e As EventArgs) Handles Button3.Click
Dim rows() As DataRow = dt.Select("PK='test row'")
If rows.Length = 0 Then
MsgBox("row was deleted already")
Else
MsgBox(rows(0)(0)) ' display PK
If MsgBox("Delete " & rows(0)(0), vbYesNo) = MsgBoxResult.Yes Then
rows(0).Delete()
End If
End If
End Sub
Note that rows(0) is the first record of the result from the select - not the record index in the overall table.