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HomeBackend DevelopmentPHP Tutorialprint_r为何多输出一个1?该怎么处理

print_r为何多输出一个1?
奇怪,第一次看到这样子。


PHP code
<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->class test    {        public $test = array();                function test()        {            $this -> test[] = 'ok';        }        function _echo()        {            foreach ($this -> test as $val)                echo print_r($val);        }            }    $test = new test();    $test -> _echo();


打印出 ok1


------解决方案--------------------
bool print_r ( mixed expression [, bool return] )
是函数当然会有返回值

对于你的应用,应写作
 echo print_r($val, 1);
------解决方案--------------------
print_r
(PHP 4, PHP 5)
print_r -- 打印关于变量的易于理解的信息。 
描述
bool print_r ( mixed expression [, bool return] )
---------------------------------------------
既然print_r何必还要echo,如需要也得加上第二个参数

PHP code
echo print_r($var,true);<br><font color="#e78608">------解决方案--------------------</font><br>1 是print_r()函数的返回值<div class="clear">
                 
              
              
        
            </div>
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