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isset()为NULL不返回任何内容

if-statement web-services laravel php

0

RAUSHAN KUMAR · 技术社区 · 8 年前

我已经写了这个php代码

//check if user has active plan and search keyword is not empty
    if (!empty($request['advertisername']) && ($userSubscriptionType == env('AMEMBER_STD_PLAN_CODE') || $userSubscriptionType == env('AMEMBER_PRE_PLAN_CODE'))) {
        $advertisername = 'LOWER(post_owner) like "%' . strtolower($request["advertisername"]) . '%"';
    } else {
        //if search keyword is null, means page is loaded for first time
        if (!isset($request['advertisername'])) {
            $advertisername = "true";
        } else {//if search keyword is not null, and user has not active plan
            $response->code = 400;
            $response->msg = "Permission issues";
            $response->data = "";
            return json_encode($response);
        }
    }

在这里 $request['advertisername']=null 来自弗罗宁。所以这个条件是真的 if (!isset($request['advertisername'])) { . 但不幸的是,它总是会持续一个街区。

如果我保存 $request['advertisername'] 在这样的变量中。那么这个条件 if (!isset($advertiserName)) { 成为现实。

//check if user has active plan and search keyword is not empty
if (!empty($request['advertisername']) && ($userSubscriptionType == env('AMEMBER_STD_PLAN_CODE') || $userSubscriptionType == env('AMEMBER_PRE_PLAN_CODE'))) {
    $advertisername = 'LOWER(post_owner) like "%' . strtolower($request["advertisername"]) . '%"';
} else {
    //if search keyword is null, means page is loaded for first time
    $advertiserName=$request['advertisername'];
    if (!isset($advertiserName)) {
        $advertisername = "true";
    } else {//if search keyword is not null, and user has not active plan
        $response->code = 400;
        $response->msg = "Permission issues";
        $response->data = "";
        return json_encode($response);
    }
}

我通过var_dump()检查了条件。任何人都能解释为什么会这样?

3 回复 | 直到 8 年前

1

Mehdi Alipour 8 年前

is_null() 而不是 !isset() .

2

1

kmdm 8 年前

您可以改用array\u key\u exists():

if (!array_key_exists('advertisername', $request)) {

请注意,iSet()的PHP手册中说:

isset â Determine if a variable is set and is not NULL

3

1

Gopal Panadi 8 年前

一个好方法是检查变量是否为空,因为它同时检查isset和null

eg if(!empty($your_variable) {    /** your code here **/   }