Home php教程 php手册 小结:几点提高php序运行效率的方法

小结:几点提高php序运行效率的方法

Jun 21, 2016 am 09:01 AM
arr foreach key while

1、用i+=1代替i=i+1。符合c/c++的习惯,效率还高。

2、尽可能的使用PHP内部函数。自己编写函数之前要详细查阅手册,看有没有相关的函数,否则费力不讨好。

3、能使用单引号字符串尽量使用单引号字符串。单引号字符串的效率要高于双引号字符串。

4、用foreach代替while遍历数组。遍历数组时foreach的效率明显高于while循环,而且不需要调用reset函数。两种遍历方法如下:

reset ($arr);
while (list($key, $value) = each ($arr)) {
echo "Key: $key; Value: $value
n";
}
foreach ($arr as $key => $value) {
echo "Key: $key; Value: $value
n";
}

以上几点均经过笔者的测试,不足之处,请多指正。



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