解析php中var_dump,var_export,print_r三个函数的区别

Adelaide ·

更新时间:2024-09-20

· 786 次阅读

下面的示例看看这三个函数的具体的区别，其中var_dump和var_export比较少用，但他们两者又很相似。所以可以看看：
代码如下:
<?php
$a = array(1,1,32,322,3433,array(32,232,23232));
$b = 1234;
$c = "alsdfl;asdf";
$d = 'a';
$e = fopen("slsl.txt", "r");
var_dump($a);
echo " ";
var_dump($b);
echo " ";
var_dump($c);
echo " ";
var_dump($d);
echo " ";
var_dump($e);
echo " ";
echo " ";
echo " ";
echo " ";
var_export($a);
echo " ";
var_export($b);
echo " ";
var_export($c);
echo " ";
var_export($d);
echo " ";
var_export($e);
echo " ";
echo " ";
echo " ";
echo " ";
print_r($a);
echo " ";
print_r($b);
echo " ";
print_r($c);
echo " ";
print_r($d);
echo " ";
print_r($e);
echo " ";

输出：
代码如下:
Warning: fopen(slsl.txt) [function.fopen]: failed to open stream: No such file or directory in E:\mywww\yangtest\base1.php on line 6
array(6) { [0]=> int(1) [1]=> int(1) [2]=> int(32) [3]=> int(322) [4]=> int(3433) [5]=> array(3) { [0]=> int(32) [1]=> int(232) [2]=> int(23232) } }
int(1234)
string(11) "alsdfl;asdf"
string(1) "a"
bool(false)
array ( 0 => 1, 1 => 1, 2 => 32, 3 => 322, 4 => 3433, 5 => array ( 0 => 32, 1 => 232, 2 => 23232, ), )
1234
'alsdfl;asdf'
'a'
false
Array ( [0] => 1 [1] => 1 [2] => 32 [3] => 322 [4] => 3433 [5] => Array ( [0] => 32 [1] => 232 [2] => 23232 ) )
1234
alsdfl;asdf
a

现在可以看到效果了，注意，最后一个不是我没有粘贴过来，而是他本来就没有显示什么东西。
您可能感兴趣的文章:php中strstr、strrchr、substr、stristr四个函数的区别总结PHP中exec函数和shell_exec函数的区别PHP中的排序函数sort、asort、rsort、krsort、ksort区别分析PHP函数addslashes和mysql_real_escape_string的区别PHP包含文件函数include、include_once、require、require_once区别总结详解PHP中strlen和mb_strlen函数的区别php中sprintf与printf函数用法区别解析PHP echo,print,printf,sprintf函数之间的区别与用法详解解析php addslashes()与addclashes()函数的区别和比较解析php函数method_exists()与is_callable()的区别PHP中函数rand和mt_rand的区别比较PHP易混淆函数的区别及用法汇总

print dump export 函数 print_r var PHP