VB.NET String.IsNullorEmpty()
Posted by asp.net videos on Saturday, February 5, 2011 · Leave a Comment
Premium (Not Free) Video Tutorials
Free Video Tutorials & Free Tools
Premium (Not Free) Video Tutorials
Free Video Tutorials & Free Tools
VB.NET StringIsNullorEmpty Example – Code Sample Syntax
Abstract: – Illustrates using VB.NET StringIsNullorEmpty Code Example.
*** 2. StringIsNullorEmpty Syntax ***
Purpose:
Returns a Boolean value that indicates if the string is Null or Empty.
Syntax:
String.IsNullorEmpty(stringtocheck)
Parameters |
Description |
stringtocheck |
Required – string that you want to check
whether it is null or empty
|
Result Data Type |
Description |
Boolean |
Returns a Boolean value that indicates if the string is Null or Empty.
|
*** 3. StringIsNullorEmpty – Quick Example ***
|
Dim strIsNullorEmptyExample As String = “This is a test string”
Console.WriteLine(String.IsNullOrEmpty(strIsNullorEmptyExample)) ‘Returns False
|
*** 4. StringIsNullorEmpty – Full Example ***
StringIsNullorEmpty Example Output Screenshot
Step 1: Click Visual Basic to Cut-n-paste code into clsStringIsNullorEmpty.vb
Public Class clsStringIsNullorEmpty
Public Sub Main()
'****************************************************************************************
' Purpose: Returns a Boolean value that indicates if the string is Null or Empty.
'
' Syntax: String.IsNullorEmpty(stringtocheck)
'
' Parameter1: stringtocheck - Required - string that you want to check
' whether it is null or empty
'
' Result: Boolean - Returns a Boolean value that indicates if the string is Null or Empty.
'
' Quick Example: Dim strIsNullorEmptyExample As String = "This is a test string"
' Console.WriteLine(String.IsNullOrEmpty(strIsNullorEmptyExample)) 'Returns False
'
'****************************************************************************************
'****************************************************************************************
' Example #1: String.IsNullorEmpty(string)
'****************************************************************************************
'****************************************************************************************
' Example #1: String.IsNullorEmpty(string)
' Returns a Boolean value that indicates if the string is Null or Empty.
'****************************************************************************************
Console.WriteLine("Example #1: String.IsNullorEmpty ")
Dim strIsNullorEmptyExample As String = "This is a test string"
Console.WriteLine(String.IsNullOrEmpty(strIsNullorEmptyExample)) 'Returns False
'write blank line to make output easier to read
Console.WriteLine()
'Prevent console from closing before you press enter
Console.ReadLine()
End Sub
End Class |
Public Class clsStringIsNullorEmpty
Public Sub Main()
'****************************************************************************************
' Purpose: Returns a Boolean value that indicates if the string is Null or Empty.
'
' Syntax: String.IsNullorEmpty(stringtocheck)
'
' Parameter1: stringtocheck - Required - string that you want to check
' whether it is null or empty
'
' Result: Boolean - Returns a Boolean value that indicates if the string is Null or Empty.
'
' Quick Example: Dim strIsNullorEmptyExample As String = "This is a test string"
' Console.WriteLine(String.IsNullOrEmpty(strIsNullorEmptyExample)) 'Returns False
'
'****************************************************************************************
'****************************************************************************************
' Example #1: String.IsNullorEmpty(string)
'****************************************************************************************
'****************************************************************************************
' Example #1: String.IsNullorEmpty(string)
' Returns a Boolean value that indicates if the string is Null or Empty.
'****************************************************************************************
Console.WriteLine("Example #1: String.IsNullorEmpty ")
Dim strIsNullorEmptyExample As String = "This is a test string"
Console.WriteLine(String.IsNullOrEmpty(strIsNullorEmptyExample)) 'Returns False
'write blank line to make output easier to read
Console.WriteLine()
'Prevent console from closing before you press enter
Console.ReadLine()
End Sub
End Class
Step 2: Click Visual Basic to Cut-n-paste code into Module1.vb
Module Module1
Sub Main()
Dim myclsStringIsNullorEmpty As New clsStringIsNullorEmpty
myclsStringIsNullorEmpty.Main()
End Sub
End Module |
Module Module1
Sub Main()
Dim myclsStringIsNullorEmpty As New clsStringIsNullorEmpty
myclsStringIsNullorEmpty.Main()
End Sub
End Module
Prerequistes:
- Install Visual Basic (Express or Standard Edition)
- Install SQL Server Express
- Download Northwind and pubs Database
- Attach Northwind Database to Databases in Sql Express
- Attach pubs Database to Databases in Sql Express
Notes:
- Console Application is used to simplify things, but Windows Forms or Web Forms could also be used
- You can build a library of syntax examples by using same project over and over and just commenting out what you do not want to execute in Module1.vb
Instructions:
- Use Visual Basic 2010 Express or Standard Edition
- Create new project;
- Click File/New Project
- Select Console Application Template
- Select Visual Basic for Language
- name of project could be VBNET_Syntax.
- Add New folder named “StringManipulation”
- Right-click project name in solution explorer;
- add new folder;
- name of folder could be: StringManipulation
- Add Class Named clsStringIsNullorEmpty to StringManipulation folder
- Right-click StringManipulation folder;
- add new item;
- Select class
- Class name could be clsStringIsNullorEmpty
- Click on Visual Basic in code in step 1 above to copy code into clsStringIsNullorEmpty.vb
- Click on Visual Basic in code in step 2 above to copy code into Module1.vb
- Click green arrow or press F5 to run program
|