VB.Net - Loops
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 −
VB.Net provides following types of loops to handle looping requirements. Click the following links to check their details.
| Loop Type |
Description |
|---|
Do Loop |
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. |
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 While |
It executes a series of statements as long as a given condition is True. |
With... End With |
It is not exactly a looping construct. It executes a series of statements that repeatedly refer to a single object or structure. |
Nested loops |
You 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 Statement |
Description |
Exit statement |
Terminates the loop or select case statement and transfers execution to the statement immediately following the loop or select case. |
Continue statement |
Causes the loop to skip the remainder of its body and immediately retest its condition prior to reiterating. |
GoTo statement |
Transfers control to the labeled statement. Though it is not advised to use GoTo statement in your program. |
