IntroductionAlmost everything in a PHP script is an expression. Anything that has a value is an expression. In a typical assignment statement ($x=100), a literal value, a function or operands processed by operators is an expression, anything that appears to the right of assignment operator (=)Syntax$x=100; //100 is an expression ... Read More

IntroductionThe goto statement is used to send flow of the program to a certain location in the code. The location is specified by a user defined label. Generally, goto statement comes in the script as a part of conditional expression such as if, else or case (in switch construct)Syntaxstatement1; statement2; ... Read More

IntroductionConditional execution of one or more statements is a most important feature of any programming language. PHP provides this ability with its if, else and elseif statements. Primary usage of if statement is as follows −Syntaxif (expression)    statement;The expression in front of if keyword is a logical expression, evaluated ... Read More

IntroductionIf name of a variable has parentheses (with or without parameters in it) in front of it, PHP parser tries to find a function whose name corresponds to value of the variable and executes it. Such a function is called variable function. This feature is useful in implementing callbacks, function ... Read More

IntroductionPHP has a large number of built-in functions such as mathematical, string, date, array functions etc. It is also possible to define a function as per specific requirement. Such function is called user defined function.A function is a reusable block of statements that performs a specific task. This block is ... Read More

IntroductionA function in PHP can be defined to accept input from calling environment/script in the form of arguments. These arguments are given as comma separeted list inside the parentheses in front of name of function. Note that while calling a function, same number of arguments must be passed to it.PHP ... Read More

IntroductionThe purpose of return statement in PHP is to return control of program execution back to the environment from which it was called. Upon returning, execution of expression following the one which invooked other function or module.If return statement occurs inside a function, execution of current function is terminated, handing ... Read More

IntroductionThe require_once statement in PHP is similar in functioning to that of require statement. Only difference is, if a file has been already included for processing, it will not be included again.Note that a file included with either include or require statement will also be not included again even if require_once ... Read More

IntroductionEffect of require statement is similar to include statement in PHP. However, there is one main difference. If the parser fails to find required file, it produces a fatal error thereby termination of current script. The include statement on the other hand emits a warning in case of failure to ... Read More

IntroductionJust as the include statement, include_once also transfers and evaluates script written in one file in another, the difference in two lies in the fact that include_once prevents same file from reloading if already done. As the name indicates, a file will be included only once even if one tries ... Read More