小编The*_*lob的帖子

在我工作的许多项目中,我发现我有嵌套for循环(我将专注于PHP实现,但也适用于javascript)采用这种通用形式:

$array1 = array(........);
$count1 = count($array1);

$invalidState = false;//An invalid state will be looked for in the innermost loop, and if found, break all the loops

for($i = 0; $i < $count1; $i++) {
    //parsing, then another loop
    $array2 = explode("needle", $array1[$i]);
    $count2 = count($array2);
    for($j = 0; $j < $count2; $j++) {
        //parsing, then sometimes even another another loop
        $array3 = explode("different-needle", $array2[$j]);
        $count3 = count($array3);
        for($k = 0; $k < $count3; $k++) {
            //check for …

对于我的一个应用程序,我假设比较2个字符串的第一个字符比比较整个字符串的相等性要快.例如,如果我知道只有2个可能的字符串(在一组n个字符串中)可以以相同的字母开头(假设是'q'),如果是这样,它们是相同的字符串,那么我可能会写一个比较如此如下:

if ($stringOne[0] === $stringTwo[0]) $qString = true;

代替:

if ($stringOne === $stringTwo) $qString = true;

但我最近写了一些基准脚本,看起来我错了.也就是说,第二次比较看起来平均比第二次快2-4倍.我的基准看起来像这样:

$x = 'A really really looooooooooooong string';
$y = 'A really really looooooooooooong string';

$timeArray = array();

//Method 1, two-four times faster than Method 2
for($i = 0; $i < 100; $i++) {
    $t1 = microtime(true);
    for($j = 0; $j < 100000; $j++) {
        if ($x === $y) continue;
    }
    $t2 = microtime(true);
    $timeArray[] = $t2 - $t1;
}

echo array_sum($timeArray) …

我有这个json编码的字符串

{"allresponses":"{\"id\":\"123456\",\"recipients\":1}"}

我只需要获取id并将其传递给php变量.

这就是我正在尝试的:假设我在变量返回中有该字符串,所以:

$return = '{"allresponses":"{\"id\":\"123456\",\"recipients\":1}"}';
$getid = json_decode($return,true);
echo $getid[0]['id'];

这不起作用; 我得到了致命的错误.你能告诉我为什么吗？怎么了？

在Firefox和Chrome中,我的php($ _GET)正在接收数字和字母以及特殊字符(例如" - "和"("),但字符除外+.这是我的ajax请求:

function ajaxFunction(param) {
var ajaxRequest;
try {
    ajaxRequest = new XMLHttpRequest();
} catch (e1) {
    try {
        ajaxRequest = new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e2) {
        try {
            ajaxRequest = new ActiveXObject("Microsoft.XMLHTTP");
        } catch (e3) {
            alert("Something is wrong here. Please try again!");
            return false;
        }
    }
}
ajaxRequest.onreadystatechange = function () {
    if (ajaxRequest.readyState === 4) document.getElementById("myDiv").innerHTML = ajaxRequest.responseText;
};

ajaxRequest.open("GET", "AJAX_file.php?param=" + param, true);
ajaxRequest.send(null);
}

当用户单击按钮调用ajaxFunction()时,用户首先在单击按钮之前填写输入类型="text".如上所述,在Firefox和Chrome中,我的php文件正在接收数字和字母以及特殊字符(例如" - ","("和")")(AJAX_file.php;非常简洁的代码版本如下但你得到了要点)并成功回应:

<?php include 'connect.php';
//Lots …

我有控制器：

class Comments extends Controller 
{
    public function GenerateComments($id)
    {
        $theme = DB::table('New_Themes')
                   ->where('id', $id)
                   ->get();

        $Comments = NewTheme_Comment::where('id_theme',  $id)->get();

        $array = $this->tree($Comments);

        function tree($Comments, $parent_id = 0, $level=0, $c=0) 
        {
            global $var;
            global $array;
            global $m;

            foreach($Comments as $Comment) 
            {
                if ($Comment['parent_id'] == $parent_id) {

                    $m++;

                    $array[$m][0]=$Comment['id'];

                    If ($level > $var)  {$var++; $array[$m][1]=0;} else {  

                        if ($c < 0) $array[$m][1]=$var-$level+1; else {$c--; $array[$m][1]=0;};
                            $var=$level; 
                };

                tree($Comments, $Comment['id'], $level+1,$c);
            }
        };

        return $this->$array;
    };

    return view('comments', ['Themes'=> $theme, 'Comments'=> $Comments, …