Question

我遇到了一个问题，我正在尝试查询一个表并获得一些结果，如果没有结果（空）那么它只是回显它是空的。

问题是，while($row = mysqli_fetch_assoc($result)) echo之前没有问题。但当它在while循环中时，它不会回复任何东西，甚至不回复if(mysqli_num_rows($result)==0)echo 'There is nothing';或者如果我这样做

if(empty($result)){
echo "There is no";

以下是我的代码，感谢您的时间

<?php
ini_set('display_errors', 1); error_reporting(E_ALL);
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);

session_start();
include 'connect.php';


echo "It is working";

$Listingid = "648";


echo "$Listingid";


$result = mysqli_query($con,"SELECT * FROM list WHERE Listingid = '$Listingid'")
    or die(mysqli_error($con));


while ($row = mysqli_fetch_assoc($result)) {
    if(empty($result)) {
        echo "There is no";
    } else {
        echo 'User ID:' . $row['userid'] . '<br>Username:' . $row['username'] . '<br>Useremail:' . $row['useremail'];
    }
}

Answer 1

试试这个逻辑

$sql = mysqli_query($con,"select count(*) as count from list WHERE Listingid = '$Listingid'");
while($row = mysqli_fetch_array($sql))
{
    $count = $row['count'];
}

if($count == 0)
{
   echo 'it is empty';
}
else
{
$result=mysqli_query($con,"SELECT * FROM list WHERE Listingid = '$Listingid'");
while($row = mysqli_fetch_array($result))
{
    echo 'User ID:'.$row['userid'].'<br>Username:'.$row['username'].'<br>Useremail:'.$row['useremail'];
}
}

Answer 2

试试这段代码：

<?php

ini_set('display_errors', 1);
error_reporting(E_ALL);
mysqli_report(MYSQLI_REPORT_ERROR | MYSQLI_REPORT_STRICT);

session_start();
include 'connect.php';


echo "It is working";

$Listingid = "648";


echo "$Listingid";


$result = mysqli_query($con, "SELECT * FROM list WHERE Listingid = '$Listingid'");

if (mysqli_num_rows($result) == 0) {
    echo "There is no";
} else {
    while ($row = mysqli_fetch_assoc($result)) {
        echo 'User ID:' . $row['userid'] . '<br>Username:' . $row['username'] . '<br>Useremail:' . $row['useremail'];
    }
}
?>

如果<{1}} - 循环之前有数据，则会检查，因为如果找不到任何结果，它将不会通过while循环有了这个查询。

Answer 3

您是否尝试过使用mysqli_fetch_array();代替mysqli_fetch_assoc();？ mysqli_fetch_array();获取所有字段，而mysqli_fetch_assoc();返回包含行值的字段名称，而不是名称ex：

[0] => "Username", [1] =>"Email"

mysqli_fetch_array(); 返回：

[0] => "username", [Username] => "username, [1] => "Email", [Email] => "Email"

和这部分：

if(empty($result)) {
    echo "There is no";
}

是没用的，因为如果没有一行，那么循环就不会出现在脚本的这一点上。

当它为空时，Php查询不返回任何甚至不返回if语句的回声

3 个答案: