PHP循环语句笔记(foreach,list)_PHP
一般foreach用的比较多
复制代码 代码如下:
$price=array('apple'=>10,'orange'=>20,'banner'=>30);
foreach($price as $key=>$value)
{
echo $key.'=>'.$value.'
';
}
echo '
';
?>
还有个更高级和常见的方法
复制代码 代码如下:
$shuiguo=array('apple'=>10,'orange'=>20,'banner'=>30);
while(list($changpin,$jiage)=each($shuiguo))
{
echo "$changpin=>$jiage".'
';
}
?>
以前还真没怎么关注下,今天自己动手,还不错,又了解新的东西了,还是自己太菜了,哎
list()函数可以用来一个数组分解成一系列的值,允许为新变量命名。不懂list的点击这里
两段代码输出是一样。
需要注意的是,当使用each()函数时候,数组将记录当前元素。如果希望在相同的脚本中使用两次该数组。就需要使用reset()降当前元素重新设置到数组开始处。
复制代码 代码如下:
$price=array('apple'=>10,'orange'=>20,'banner'=>30);
foreach($price as $key=>$value)
{
echo $key.'=>'.$value.'
';
}
echo '
';
reset($price);
while(list($key,$value)=each($price))
{
echo "$key=>$value","
";
}
?>
这样就可以依然使用数组$price咯。
书上有的,作为新手的我,自己动手,敲下看看效果,理解下,写个帖子,方便以后忘记了看看,说的比较肤浅,语言表达不好,见笑了。
复制代码 代码如下:
/*
*PHP中的循环语句学习笔记
*一.while循环
if(表达式)
只执行一次一条语句。
while(表达式){
反复执行这个循环体;
}
*二.do-while循环
*三.for循环
*根据循环条件不同有两种类型的循环
*一种:计数循环 for
*另外一种:条件型循环 while do-while //foreach
*几个和循环有关的语句
*break;//可以用于流程控制和循环体,跳出循环。
continue;//只能用于循环体,退出本次循环。 exit;
return;
*写循环尽量不要超过三层。
*循环的流程控制语句尽量不要超过五层。
*/
$num=0;
while($numecho "这是执行第 {$num} 次输出的结果
";
$num++;
}
//
echo '
'.$i.' | ';
//
$i=0;
do{
echo "$i :this is do*while
";
$i++;
}while($i//
for(初始化的条件;条件表达式;增量){
循环体;
}
/*
do-while循环就是先执行一次代码,然后判断,而
while循环就是先判断,如果为true就继续循环,为
false就不循环。
*/
//九九乘法表
for($i=1; $ifor($j=1; $jecho "$j x $i =
".$j*$i." ";
}
echo '
';

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