{"id":65157,"date":"2022-06-24T10:01:53","date_gmt":"2022-06-24T10:01:53","guid":{"rendered":"https:\/\/itsourcecode.com\/?p=65157"},"modified":"2023-11-21T05:44:31","modified_gmt":"2023-11-21T05:44:31","slug":"vb-net-loops","status":"publish","type":"post","link":"https:\/\/itsourcecode.com\/tutorials\/visual-basic-tutorial\/vb-net-loops\/","title":{"rendered":"VB.net Loops – For Each, Do While, While End, For Next"},"content":{"rendered":"\n

What is VB.net Loops?<\/strong><\/h2>\n\n\n\n

A VB.net Loops <\/strong>or looping statement is used to repeat the same process multiple times until it meets the specified condition in a program. <\/p>\n\n\n\n

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By using a loop <\/strong>in a program, a programmer can repeat any number of statements up to the desired number of repetitions.<\/p>\n\n\n\n

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There can be instances where you need to run a block of code repeatedly. <\/p>\n\n\n\n

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The first statement in a function is executed first, then the second, and so on. In general, statements are executed in order.<\/p>\n\n\n\n

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The general form of a loop statement in most programming languages is as follows. A loop statement allows us to run a statement or collection of statements several times.<\/p>\n\n\n\n

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VB.net Loops Flow Chart<\/strong>:<\/h3>\n\n\n
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\"VB<\/a>
VB NET Loops Diagram<\/figcaption><\/figure><\/div>\n\n\n

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Types of Loop in VB.net<\/strong><\/h2>\n\n\n\n

VB.net<\/strong> provides the following types of loops<\/strong> to handle looping requirements.<\/p>\n\n\n\n

Loop Types in VB.net<\/th>Description<\/th><\/tr>
Do Loop<\/td>It repeats the enclosed block of statements while a Boolean condition is True or until the condition becomes True. It could be terminated at any time with the Exit Do statement.<\/td><\/tr>
For…Next<\/td>It repeats a group of statements a specified number of times and a loop index counts the number of loop iterations as the loop executes.<\/td><\/tr>
For Each…Next<\/td>It repeats a group of statements for each element in a collection. This loop is used for accessing and manipulating all elements in an array or a VB.Net collection.<\/td><\/tr>
While… End While<\/td>It executes a series of statements as long as a given condition is True.<\/td><\/tr><\/tbody><\/table>
Types of Loop in VB.net<\/em><\/strong><\/figcaption><\/figure>\n\n\n\n

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Do Loop in VB.net<\/strong><\/h3>\n\n\n\n

The Do While loop In VB.NET<\/strong> is used to execute blocks of statements in the program, as long as the condition remains true. <\/p>\n\n\n\n

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It is similar to the While End Loop<\/strong>, but there is a slight difference between them. <\/p>\n\n\n\n

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The while loop<\/strong> initially checks the defined condition, if the condition becomes true, the while loop’s statement is executed. <\/p>\n\n\n\n

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Whereas in the Do loop<\/strong>, is the opposite of the while loop, which means that it executes the Do statements<\/strong>, and then it checks the condition.<\/p>\n\n\n\n

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Syntax:<\/strong><\/h4>\n\n\n\n
Do  \n[ Statements to be executed]  \nLoop While Boolean_expression  \n\/\/ or  \nDo   \n[Statement to be executed]  \nLoop Until Boolean_expression  <\/code><\/pre>\n\n\n\n
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In the above syntax, the Do keyword follows a block of statements, and the While keyword checks Boolean_expression<\/strong> after the execution of the first Do statement.<\/p>\n\n\n\n
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 Data Flow Diagram:<\/strong><\/h4>\n\n\n
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\"Do<\/a>
Do Loop Data Flow Diagram in VB NET<\/figcaption><\/figure><\/div>\n\n\n
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The above flow chart represents the flow of the Do While loop<\/strong>. <\/p>\n\n\n\n
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It is used to control the flow of statements, such that it executes the statement at least once before checking the While or Until condition. <\/p>\n\n\n\n
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If the condition is true, the next iteration will be executed till the condition becomes false.<\/p>\n\n\n\n
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Example Program of Do Loop in VB.net<\/strong><\/h4>\n\n\n\n
Example 1<\/strong>. Write a simple program to print a number from 1<\/strong> to 10<\/strong> using the Do While loop in VB.net<\/strong>.<\/p>\n\n\n\n
Imports System  \nModule Do_loop  \n    Sub Main()  \n        ' Initializatio and Declaration of variable i  \n        Dim i As Integer = 1  \n        Do  \n            ' Executes the following Statement  \n            Console.WriteLine(\" Value of variable I is : {0}\", i)  \n            i = i + 1 'Increment the variable i by 1  \n        Loop While i <= 10 ' Define the While Condition  \n  \n        Console.WriteLine(\" Press any key to exit...\")  \n        Console.ReadKey()  \n    End Sub  \nEnd Module  <\/code><\/pre>\n\n\n\n
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When the above code is compiled and executed, it produces the following result:<\/p>\n\n\n\n
Value of variable I is : 1
Value of variable I is : 2
Value of variable I is : 3
Value of variable I is : 4
Value of variable I is : 5
Value of variable I is : 6
Value of variable I is : 7
Value of variable I is : 8
Value of variable I is : 9
Value of variable I is : 10
Press any key to exit\u2026<\/p>\n\n\n\n
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In the above program, the Do While loop<\/strong> executes the body until the given condition becomes false<\/em><\/strong>. <\/p>\n\n\n\n
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When the condition becomes false<\/strong><\/em> the loop will be terminated.<\/p>\n\n\n\n
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You can test the above example here! \u27a1 VB.net Online Compiler<\/a><\/strong><\/p>\n\n\n\n
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For the Next Loop in VB.net<\/strong><\/h3>\n\n\n\n
A For Next loop in VB.net<\/strong> is used to repeatedly execute a sequence of code or a block of code until a given condition is satisfied. <\/p>\n\n\n\n
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A For loop<\/strong> is useful in such a case when we know how many times a block of code has to be executed. In VB.NET, the For loop<\/strong> is also known as For Next Loop<\/strong>.<\/p>\n\n\n\n
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Syntax:<\/strong><\/h4>\n\n\n\n
'syntax of for next loop'\n\nFor variable_name As [ DataType ] = start To end [ Step step ]  \n[ Statements to be executed ]  \nNext  <\/code><\/pre>\n\n\n\n
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Let’s Understand the Next Loop in Detail.<\/p>\n\n\n\n
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  1. For<\/strong>: It is the keyword that is present at the beginning of the definition.<\/li>\n<\/ol>\n\n\n\n
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    1. variable_name<\/strong>: It is a variable name, which is required in the For loop Statement. The value of the variable determines when to exit from the For-Next loop<\/strong>, and the value should only be numeric.<\/li>\n<\/ol>\n\n\n\n
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      1. [Data Type]<\/strong>: It represents the Data Type of the variable_name<\/strong>.<\/li>\n<\/ol>\n\n\n\n
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        1. start To end<\/strong>: The start and end are the two important parameters representing the initial and final values of the variable_name<\/strong>. \n\n\n\n\n