Convert.ToInt64 (String) converts string to 64-bit signed integer.
Module Example Public Sub Main() Dim values() As String = { "One", "1.34e28", "137", "11111.9", Int32.MaxValue.ToString() } Dim result As Long For Each value As String In values Try result = Convert.ToInt64(value) Console.WriteLine(result) Catch e As Exception Console.WriteLine("The {0} value '{1}' is not in a recognizable format.", _ value.GetType().Name, value) End Try Next End Sub End Module