MYSQL SELECT 仅查询一个数据

Question

view_products() below displays only one data from my table product which contains 20 data. Depending on where you place return $output; either inside while loop which displays the first data or outside the while loop which displays the last data.

<?php echo view_products(); ?>

$dbhost = "localhost";
$dbuser = "root";
$dbpass = "password@edadmin";
$dbname = "estore";
$dbconn = mysqli_connect($dbhost, $dbuser, $dbpass, $dbname);

//Test if connection occurred,
if (mysqli_connect_errno()) {
    die("Database connection failed: " .
        mysqli_connect_error() .
        " (" . mysqli_connect_errno() . ")");
}

function view_products()
{
    global $dbconn;

    $sql = "SELECT * FROM product";
    $result = mysqli_query($dbconn, $sql);

    
    if (mysqli_num_rows($result) > 0) {
        while ($products = mysqli_fetch_assoc($result)) {
            $output = "<div class=\"col-lg-4 col-md-6 portfolio-item filter-app wow fadeInUp\">";
            $output .= "<div class=\"portfolio-wrap\"><figure>";
            $output .= "<img src=" . $products['ProductImage'] . " class=\"img-fluid\" alt=\"\">";
            $output .= "<a href="  . $products['ProductImage'] . " data-lightbox=\"portfolio\" data-title=\"App 1\" class=\"link-preview\" title=\"Preview\"><i class=\"ion ion-eye\"></i></a>";
            $output .= "</figure>";
            $output .= " <div class=\"portfolio-info\">";
            $output .= "<p><a href=\"#\">" . $products['ProductName'] . " </a></p>";
            $output .= "<p>" . "&#x20a6 " . $products['ProductAmount'] . "</p>";
            $output .= "</div></div></div>";
            return $output;
        }
    } else {
        return "No product yet";
    } // return $output;
}

Answer 1

The reason is that you are resetting the content of $output in the first line of your loop $output = "<div class=\"col-lg-4 col-md-6 portfolio-item filter-app wow fadeInUp\">"; So if you put the return at the end of the loop, in the first loop it will return the first record and exit the function, if you put it at the end of the function, in each loop $output will be cleared and the content of that loop will only be written in $output so at the end of the function you will only have the content of the last loop in $output

What you can to is to set $output to an empty string and then just append everything in your loop. Also set the value of $output in the else block and then at the end return $output

function view_products()
{
global $dbconn;

    $sql = "SELECT * FROM product";
    $result = mysqli_query($dbconn, $sql);

    
    if (mysqli_num_rows($result) > 0) {
        $output = "";
        while ($products = mysqli_fetch_assoc($result)) {
            $output .= "<div class=\"col-lg-4 col-md-6 portfolio-item filter-app wow fadeInUp\">";
            $output .= "<div class=\"portfolio-wrap\"><figure>";
            $output .= "<img src=" . $products['ProductImage'] . " class=\"img-fluid\" alt=\"\">";
            $output .= "<a href="  . $products['ProductImage'] . " data-lightbox=\"portfolio\" data-title=\"App 1\" class=\"link-preview\" title=\"Preview\"><i class=\"ion ion-eye\"></i></a>";
            $output .= "</figure>";
            $output .= " <div class=\"portfolio-info\">";
            $output .= "<p><a href=\"#\">" . $products['ProductName'] . " </a></p>";
            $output .= "<p>" . "&#x20a6 " . $products['ProductAmount'] . "</p>";
            $output .= "</div></div></div>";
        }
    } else {
        $output = "No product yet";
    } // return $output;
    return $output;
}