php数组(一)
php的数组索引是从0开始,而不是1.
$states[0] //普通数组可以用序号作为键$states['aa'] //关联数组用键值对来调用$states['aa']['aaa'] //多为数组可以通过这种方式来调用
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php中无论使用关联数组还是数值键,都是依赖于一种数组指针的特性,数组指针就如同书签,告诉你正在检查的数组位。
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你并不是直接操作数组指针,而是使用内置的语言特性或函数来遍历数组
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这里的意思就是在php里面,所有的数组管理方法其实都是在操作数组指针,只是操作指针的方法都是php内置好或者被函数封装好的。
创建数组
直接创建
$states[0] = 1;$states[] = 1;$states['aa'] = 1;
用array()创建数组
$languages = array('spain'=>'spanish','ireland'=>'english');
用list提取数组
文件users.txt内容a|b|c$users = fopen('users.txt','r');while($line = fgets($users,4096)){ list($name,$sex,$age) = explode("|",$line); //通过explode将|作为分隔符,然后分成3份,然后再用list将这3份分别代入到3个变量里面}echo $name;echo $sex;echo $age;
用range来生成数组
$test = range(1,6); //生成值为1到6的6个元素的数组$test = range(1,10,2); //第三个参数是步长,步长就是大概是间隔的意思,这里生成 1 3 5 。。。。间隔为2的值
测试数组
用is_array来测试,返回true和false
打印数组
用print_r来打印
print_r($states); //遍历打印数组

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