Dim strSQL As String = "Select * from Doctors where first_name= '" & First_name.Text & "' and last_name= '" & Last_name.Text & "' "
Dim da As SqlDataAdapter = New SqlDataAdapter(strSQL, DBConn)
Dim ds As DataSet = New DataSet
da.Fill(ds)

My problem is: Last_name may contain ', for example O'Brien
the query will fail. strSQl= "select * from Doctors where last_name=O'Brien"

how can I wrote ' inside the string? for my textbox : Last_name.Text
it may contain ', what 's correct syntax to write my query?
Thanks!