PHP | print_r() Function (original) (raw)
Last Updated : 26 Apr, 2018
The print_r() function is a built-in function in PHP and is used to print or display information stored in a variable.
Syntax:
print_r( variable,variable, variable,isStore )
Parameters: This function accepts two parameters as shown in above syntax and described below.
- $variable: This parameter specifies the variable to be printed and is a mandatory parameter.
- $isStore: This an option parameter. This parameter is of boolean type whose default value is FALSE and is used to store the output of the print_r() function in a variable rather than printing it. If this parameter is set to TRUE then the print_r() function will return the output which it is supposed to print.
Return Value: If the variableisanintegerorafloatorastringthefunctionprintsthevalueofthevariable.Ifthevariableisanarraythefunctionprintsthearrayinaformatwhichdisplaysthekeysaswellasvalues,asimilarnotationisusedforobjects.Iftheparametervariable is an integer or a float or a string the function prints the value of the variable. If the variable is an array the function prints the array in a format which displays the keys as well as values, a similar notation is used for objects. If the parameter variableisanintegerorafloatorastringthefunctionprintsthevalueofthevariable.Ifthevariableisanarraythefunctionprintsthearrayinaformatwhichdisplaysthekeysaswellasvalues,asimilarnotationisusedforobjects.IftheparameterisStore is set to TRUE then the print_r() function will return a string containing the information which it is supposed to print.
Below programs illustrate the print_r() function:
Program 1:
<?php
$var1 = "Welcome to GeeksforGeeks" ;
$var2 = 101;
$arr = array ( '0' => "Welcome" , '1' => "to" , '2' => "GeeksforGeeks" );
print_r( $var1 );
echo "\n" ;
print_r( $var2 );
echo "\n" ;
print_r( $arr );
?>
Output:
Welcome to GeeksforGeeks 101 Array ( [0] => Welcome [1] => to [2] => GeeksforGeeks )
Program 2:
<?php
$arr = array ( '0' => "Welcome" , '1' => "to" ,
`` '2' => "GeeksforGeeks" );
$results = print_r( $arr , true);
echo $results ;
?>
Output:
Array ( [0] => Welcome [1] => to [2] => GeeksforGeeks )