Switching Flow

Most scripts will evaluate conditions and change their behavior accordingly. These decisions are what make your PHP pages dynamic; that is, able to change their output according to circumstances. Like most programming languages, PHP allows you to do this with an if statement.

The if Statement

An if statement is a way of controlling the execution of a statement that follows it (that is, a single statement or a block of code inside braces). The if statement evaluates an expression between parentheses. If this expression results in a true value, the statement is executed. Otherwise, the statement is skipped entirely. This enables scripts to make decisions based on any number of factors:

if (expression) { // code to execute if the ...

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