To print information about variables, arrays or objects in PHP, we can use the following functions:<\/p>\n
print_r()<\/code><\/li>\nvar_dump() <\/code><\/li>\nvar_export()<\/code><\/li>\n<\/ul>\nprint_r( )<\/strong><\/p>\nAccording to this explanation<\/a> on stackoverflow.com, print_r()<\/code>:<\/p>\n\n- Outputs a human-readable representation of any one value<\/li>\n
- Accepts not just strings but other types including arrays and objects, formatting them to be readable<\/li>\n
- Useful when debugging<\/li>\n
- May return its output as a return value (instead of echoing) if the second optional argument is given<\/li>\n<\/ul>\n
Ostensibly, the ‘r’ in print_r stands for ‘readable’. For example, setting up an associative array and using print_r to print it in a human readable format:<\/p>\n
<?php\r\n$a = array ('a' => 'apple', 'b' => 'banana', 'c' => array ('x', 'y', 'z'));\r\nprint_r ($a);\r\n?><\/pre>\nyields:<\/p>\n
Array ( [a] => apple [b] => banana [c] => Array ( [0] => x [1] => y [2] => z ) )<\/pre>\nFor more information about print_r()<\/code>, see:
\nhttp:\/\/php.net\/manual\/en\/function.print-r.php<\/a><\/p>\n <\/p>\n
\nvar_dump( )<\/strong><\/p>\nHere is what php.net says about var_dump()<\/code>:<\/p>\nThis function displays structured information about one or more expressions that includes its type and value. Arrays and objects are explored recursively with values indented to show structure.<\/p><\/blockquote>\n
According to this explanation<\/a> on stackoverflow.com, var_dump()<\/code>:<\/p>\n\n\n- Outputs a human-readable representation of one or more values separated by commas<\/li>\n
- Accepts not just strings but other types including arrays and objects, formatting them to be readable<\/li>\n
- Uses a different output format to print_r(), for example it also prints the type of values<\/li>\n
- Useful when debugging<\/li>\n
- No return value<\/li>\n<\/ul>\n<\/blockquote>\n
For example,\u00a0 let’s set up an array that contains two integers and a sub-array. var_dump()<\/code> will not only show the contents of the array, but will also show the data types and lengths of each value in the array:<\/p>\n<?php\r\n$a = array(1, 2, array(\"apple\", \"banana\", \"cherry\"));\r\nvar_dump($a);\r\n?>\r\n<\/pre>\nyields:<\/p>\n
array(3) { [0]=> int(1) [1]=> int(2) [2]=> array(3) { [0]=> string(5) \"apple\" [1]=> string(6) \"banana\" [2]=> string(6) \"cherry\" } }<\/pre>\nAnother example of using var_dump()<\/code> to get data type of a variable:<\/p>\n<?php\r\n$b = 3.1;\r\n$c = true;\r\nvar_dump($b, $c);\r\n?><\/pre>\nwhich yields:<\/p>\n
float(3.1) bool(true)<\/pre>\nFor more information about var_dump()<\/code>, see:
\nhttp:\/\/php.net\/manual\/en\/function.var-dump.php<\/a><\/p>\n <\/p>\n
\nvar_export( )<\/strong><\/p>\nHere is what php.net says about var_export()<\/code>:<\/p>\n\nvar_export<\/span> \u2014 Outputs or returns a parsable string representation of a variable<\/span><\/p>\nvar_export() gets structured information about the given variable. It is similar to var_dump() with one exception: the returned representation is valid PHP code.
\n<\/strong><\/span><\/p><\/blockquote>\nAccording to this explanation<\/a> on stackoverflow.com, var_export()<\/code>:<\/p>\n\n\n- Outputs a human-readable and PHP-executable<\/em> representation of any one<\/em> value<\/li>\n
- Accepts not just strings but other types including arrays and objects, formatting them to be readable<\/li>\n
- Uses a different output format to both
print_r()<\/code> and var_dump()<\/code> – resulting output is valid PHP code!<\/li>\n- Useful when debugging<\/li>\n
- May return its output as a return value (instead of echoing) if the second optional argument is given<\/li>\n<\/ul>\n<\/blockquote>\n
For example:<\/p>\n
<?php\r\n$a = array (1, 2, array (\"a\", \"b\", \"c\"));\r\nvar_export($a);\r\n?>\r\n<\/pre>\nwhich produces:<\/p>\n
array ( 0 => 1, 1 => 2, 2 => array ( 0 => 'a', 1 => 'b', 2 => 'c', ), )<\/pre>\nNotice the difference between this output and the output for print_r.<\/p>\n
For more information about var_export()<\/code>, see:
\nhttp:\/\/php.net\/manual\/en\/function.var-export.php<\/a><\/p>\n <\/p>\n","protected":false},"excerpt":{"rendered":"
To print information about variables, arrays or objects in PHP, we can use the following functions: print_r() var_dump() var_export() print_r( ) According to this explanation on stackoverflow.com, print_r(): Outputs a human-readable representation of any one value Accepts not just strings but other types including arrays and objects, formatting them to be readable Useful when debugging … Continue reading PHP: How to print information about variables, arrays, and objects<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[97],"tags":[69,99,100,101],"class_list":["post-1453","post","type-post","status-publish","format-standard","hentry","category-php-language","tag-php","tag-print_r","tag-var_dump","tag-var_export"],"_links":{"self":[{"href":"https:\/\/bluegalaxy.info\/codewalk\/wp-json\/wp\/v2\/posts\/1453","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/bluegalaxy.info\/codewalk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/bluegalaxy.info\/codewalk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/bluegalaxy.info\/codewalk\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/bluegalaxy.info\/codewalk\/wp-json\/wp\/v2\/comments?post=1453"}],"version-history":[{"count":17,"href":"https:\/\/bluegalaxy.info\/codewalk\/wp-json\/wp\/v2\/posts\/1453\/revisions"}],"predecessor-version":[{"id":1522,"href":"https:\/\/bluegalaxy.info\/codewalk\/wp-json\/wp\/v2\/posts\/1453\/revisions\/1522"}],"wp:attachment":[{"href":"https:\/\/bluegalaxy.info\/codewalk\/wp-json\/wp\/v2\/media?parent=1453"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bluegalaxy.info\/codewalk\/wp-json\/wp\/v2\/categories?post=1453"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bluegalaxy.info\/codewalk\/wp-json\/wp\/v2\/tags?post=1453"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}