实例7:数组值基本操作
复制代码 代码如下:
$arr=array('a'=>"你",'b'=>"我","他");
$arr[]="其他";
echo $arr['b']."
";
$arr['c']="";//给个空值,但仍然占着位置的
echo count($arr)."
";//数组有多少个值。
unset($arr['b']);//这函数可以注销字符串、整个数组等值类型和引用类型。
print_r($arr);//这函数打印数值、引用类型的整个内部结构。
echo "
";
foreach($arr as $key=>$value)
echo $key.":".$value."
";//循环输出整个数组的值。
?>
实例8:数组和字符串之间转换
复制代码 代码如下:
$arr=array('a'=>"你",'b'=>"我","他");
echo $arr=implode('-',$arr);//数组转字符串,连接符-
echo "
";
print_r(explode('-',$arr,2));//字符串转数组。如果最后一个参数不用,表示全部'-'都分割成数组
?>
实例9:数组排序
复制代码 代码如下:
$arr=array('b'=>"你",'a'=>"我","他");
ksort($arr);//数组按键值的拼音(UTF-8编码)排序,键值不会丢失。注意此排序不返回新数组而是直接把原来数组当引用传递。
print_r($arr);
echo "
";
asort($arr);//数组按值的拼音(UTF-8编码)排序,键值不会丢失。如果不要键值,可以用函数sort();如果反序也有函数rsort()。注意此排序不返回新数组而是直接把原来数组当引用传递。
print_r($arr);
echo "
";
$arr=array(10000,100,1000);
natsort($arr);//按数字自然排序值,而natcasesort()不区分大小写
print_r($arr);
echo "
";
print_r(array_reverse($arr));//数组反序
echo "
";
?>
实例10:数组、数字随机抽取、数字和编码转换
复制代码 代码如下:
$arr=array('b'=>"你",'a'=>"我","他");
$key=array_rand($arr,2);//数组随机抽取2个键值,返回含两个键值的索引数组
echo $arr[$key[0]].$arr[$key[1]];
echo "
";
echo mt_rand(60,100);//返回一个该范围内的随机整数。
echo "
";
echo chr(mt_rand(ord('a'),ord('z')));//数字和编码转换。
echo "
";
?>
数组的函数就讲完了,我只挑几个有代表性的让大家入门,其实,还有一些不常用的数组函数的。除此之外,我们可以用for或者foreach循环来处理数组,生成自己的my_函数,笨有笨方法。

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