For example, the Pascal and Lua languages have a ' repeat until' loop, which continues to run until the control expression is true (and then terminates) - whereas a 'while' loop runs while the control expression is true (and terminates once the expression becomes false). Some languages may use a different naming convention for this type of loop. When such a loop is created intentionally, there is usually another control structure (such as a break statement) that allows termination of the loop. It is possible, and in some cases desirable, for the condition to always evaluate to true, creating an infinite loop. In other words, whereas a while loop sets the truth of a statement as a condition precedent for the code's execution, a do-while loop provides for the action's ongoing execution subject to defeasance by the condition's falsity, which falsity ( i.e., the truth of the condition's negation) is set as a condition subsequent. If the expression is false, the loop terminates and control transfers to the statement following the do-while loop. This process is repeated as long as the expression evaluates to true. If it is true, the code executes the body of the loop again. Another useful control structure, the With statement, lets you run a series of statements without having to requalify an object. This means that the code must always be executed first and then the expression or test condition is evaluated. By using conditional statements and looping statements (also called control structures), you can write Visual Basic code that makes decisions and repeats actions.

Contrast with the while loop, which tests the condition before the code within the block is executed, the do-while loop is an exit-condition loop. Because do while loops check the condition after the block is executed, the control structure is often also known as a post-test loop. This repeats until the condition becomes false. If the condition is true the code within the block is executed again. First, the code within the block is executed, and then the condition is evaluated. The do while construct consists of a process symbol and a condition. In most computer programming languages, a do while loop is a control flow statement that executes a block of code at least once, and then either repeatedly executes the block, or stops executing it, depending on a given boolean condition at the end of the block.

Visual basic looping