VB.Net - Loops

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There may be a situation when you need to execute a block of code several number of times. In general, statements are executed sequentially: The first statement in a function is executed first, followed by the second, and so on.

Programming languages provide various control structures that allow for more complicated execution paths.

A loop statement allows us to execute a statement or group of statements multiple times and following is the general form of a loop statement in most of the programming languages:

Loop Architecture

VB.Net provides following types of loops to handle looping requirements. Click the following links to check their details.

Loop TypeDescription
Do LoopIt 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.
For...Next 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.
For Each...Next 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.
While... End WhileIt executes a series of statements as long as a given condition is True.
With... End WithIt is not exactly a looping construct. It executes a series of statements that repeatedly refer to a single object or structure.
Nested loopsYou can use one or more loops inside any another While, For or Do loop.

Loop Control Statements:

Loop control statements change execution from its normal sequence. When execution leaves a scope, all automatic objects that were created in that scope are destroyed.

VB.Net provides the following control statements. Click the following links to check their details.

Control StatementDescription
Exit statementTerminates the loop or select case statement and transfers execution to the statement immediately following the loop or select case.
Continue statementCauses the loop to skip the remainder of its body and immediately retest its condition prior to reiterating.
GoTo statementTransfers control to the labeled statement. Though it is not advised to use GoTo statement in your program.


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