The output statements in PHP are used to send data to the client, mainly including echo, print, printf, var_dump and var_export.
Output statements in PHP
PHP provides a variety of output statements for sending data to client. The most commonly used output statements include:
- echo
- printf
- var_dump
- var_export
echo
echo
is the simplest output statement, which can output one or more expressions. An expression can be a variable, constant, string, or any other PHP value. echo
will not return any value.
echo "Hello World!";
print
is similar to echo
, but it returns the number of bytes output.
$bytes = print("Hello World!");
printf
printf
is used to format output. It uses the same format string as the C language printf
function.
printf("My name is %s and my age is %d.", "John", 30);
var_dump
var_dump
is used for debugging purposes. It displays the contents of a variable, including its type, value, and memory address.
var_dump($myVariable);
var_export
var_export
is similar to var_dump
, but it returns a PHP code representation of the variable contents.
$myCode = var_export($myVariable);
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