Imports System
Class IsBlankOrEmpty
Public Shared Function IsBlankOrEmptyMethod(ByVal str As String) As Boolean
If String.IsNullOrEmpty(str) Then
Return True
End If
For Each ch As Char In str
If Not Char.IsWhiteSpace(ch) Then
Return False
End If
Next
Return True
End Function
Public Shared Sub Main()
Dim test1 As String = Nothing
Dim test2 As String = ""
Dim test3 As String = " "
Dim test4 As String = "abc"
Console.WriteLine("Test1: " & IsBlankOrEmptyMethod(test1))
Console.WriteLine("Test2: " & IsBlankOrEmptyMethod(test2))
Console.WriteLine("Test3: " & IsBlankOrEmptyMethod(test3))
Console.WriteLine("Test4: " & IsBlankOrEmptyMethod(test4))
End Sub
End Class
' run:
'
' Test1: True
' Test2: True
' Test3: True
' Test4: False
'