The difference between echo, print and print pur

Time:2020-2-8

1. Echo can output one or more strings separated by commas

2. Print can also output one or more strings, and multiple connectors are used

3. Print_r() can print arrays; objects

bool print_r ( mixed $expression [, bool $return ] )

Parameter Description:

$expression: the variable to be printed. If a variable of type string, integer or float is given, the variable value itself will be printed. If array is given, the keys and elements are displayed in a format. Objects are similar to arrays.
$return: optional. If true, the result will not be output, but will be assigned to a variable. If false, the result will be output directly.

4. Resolution speed echo > Print > print_r();

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