php 数组相加,看不懂,请些一个好例子给我看一下好吗
$a ="a";<br />$b ="b";<br />$ay[$a][$b][]= 3;<br />print_r($ay);<br />
输出, Array ( [a] => Array ( [b] => Array ( [0] => 3 ) ) ),意思是不是数组a中存在数组b,数组b中存在一个数组,该数组索引0的时候值是3 。
//////////////////////////////////////
$Me[$a][$b] += $Me[$k][$c]; //请问这个相加之后左边的值会变成什么样??
$Me[$z][$m] = $Me[$sy][$my]; //这个赋值之后会变成怎么样??
这两句,看得我头很大,请帮忙,最好写一个例子给我演示一下这两句,我头脑真的不太好用。。
我只懂得下面这样简单的。。
$a[] =1;
$b[] =2;
echo $a[0] + b[0];结果是3 。
也懂得
$a[] =1;
$b[] =2;
echo $a[0] = b[0]; 结果a[0]是2;
------解决方案--------------------
$Me[$a][$b] += $Me[$k][$c]; //请问这个相加之后左边的值会变成什么样??
$Me[$z][$m] = $Me[$sy][$my]; //这个赋值之后会变成怎么样??
这是二维数组的表示法,表示一个元素的值,你大可以当作一个变量:
$a += 1;
$a = 3;
这样就能看懂了吧
------解决方案--------------------
$Me[$a][$b] += $Me[$k][$c]; //请问这个相加之后左边的值会变成什么样??
这是简写,等同
$Me[$a][$b] = $Me[$a][$b]+$Me[$k][$c];
等同
$a=$a+$b;
$Me[$z][$m] = $Me[$sy][$my]; //这个赋值之后会变成怎么样??
$Me[$z][$m]和$Me[$sy][$my]都是存放一个值的位置
假如$Me[$z][$m]存放的值为1,$Me[$sy][$my]存放的值为2
那么 echo $Me[$z][$m] = $Me[$sy][$my];
结果就是 $Me[$z][$m]是2
------解决方案--------------------
php array() 是多维数组,
1维的取值方式是:array[]
2维的取值方式是:array[][]
以此类推。
可以这样返回数组的维度。
<br />/** <br /> * 返回数组的维度 <br /> * @param [type] $arr [description] <br /> * @return [type] [description] <br /> */<br />function arrayLevel($arr){ <br /> $al = array(0); <br /> function aL($arr,&$al,$level=0){ <br /> if(is_array($arr)){ <br /> $level++; <br /> $al[] = $level; <br /> foreach($arr as $v){ <br /> aL($v,$al,$level); <br /> } <br /> } <br /> } <br /> aL($arr,$al); <br /> return max($al); <br />} <br /><br />$arr = array( <br /> '0'=>'0', <br />); <br /><br />echo arrayLevel($arr); <br />
------解决方案--------------------
合并数组建议采用php array自带的函数 array_merge()http://www.w3school.com.cn/php/func_array_merge.asp
------解决方案--------------------
多动手,少动眼,记得给脑子加点油
$Me = array(<br /> array(1, 2, 3, 4),<br /> array(4, 6, 7, 8),<br /> array(9, 10, 11, 12),<br /> array(13, 14, 15, 16),<br />);<br />$a = 0;<br />$b = 1;<br />$k = 2;<br />$c = 3;<br />$z = 3;<br />$m = 3;<br />$sy = 1;<br />$my = 2;<br />$Me[$a][$b] += $Me[$k][$c];<br />$Me[$z][$m] = $Me[$sy][$my];<br />print_r($Me);

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