在实时ajax搜索中搜索时出现致命错误

Question

I'm using a live AJAX search for my website.

I downloaded the script from ninetofive.me/data/tutorials/live-search/.

When I search, I get Fatal error: Call to a member function fetch_array() on a non-object in E:\xampp\htdocs\test\ajaxsearch\search.php on line 54.

I didn't make any changes in the demo script other than changing the MySQL credentials.

Here is my search.php:

<?php
// Credentials
$dbhost = "localhost";
$dbname = "testdb";
$dbuser = "root";
$dbpass = "";

//  Connection
global $tutorial_db;

$tutorial_db = new mysqli();
$tutorial_db->connect($dbhost, $dbuser, $dbpass, $dbname);
$tutorial_db->set_charset("utf8");

//  Check Connection
if ($tutorial_db->connect_errno) {
    printf("Connect failed: %s
", $tutorial_db->connect_error);
    exit();
    }

/************************************************
    Search Functionality
************************************************/

// Define Output HTML Formating
$html = '';
$html .= '<li class="result">';
$html .= '<a target="_blank" href="urlString">';
$html .= '<h3>nameString</h3>';
$html .= '<h4>functionString</h4>';
$html .= '</a>';
$html .= '</li>';

// Get Search
$search_string = preg_replace("/[^A-Za-z0-9]/", " ", $_POST['query']);
$search_string = $tutorial_db->real_escape_string($search_string);

// Check Length More Than One Character
if (strlen($search_string) >= 1 && $search_string !== ' ') {
    // Build Query
    $query = 'SELECT * FROM search WHERE function LIKE "%'.$search_string.'%" OR name LIKE "%'.$search_string.'%"';

    // Do Search
    $result = $tutorial_db->query($query);
    while($results = $result->fetch_array()) {
        $result_array[] = $results;
    }
// Check If We Have Results
if (isset($result_array)) {
    foreach ($result_array as $result) {
    // Format Output Strings And Hightlight Matches
    $display_function = preg_replace("/".$search_string."/i", "<b class='highlight'>".$search_string."</b>", $result['function']);
    $display_name = preg_replace("/".$search_string."/i", "<b class='highlight'>".$search_string."</b>", $result['name']);
    $display_url = 'http://php.net/manual-lookup.php?pattern='.urlencode($result['function']).'&lang=en';

    // Insert Name
    $output = str_replace('nameString', $display_name, $html);

    // Insert Function
    $output = str_replace('functionString', $display_function, $output);

            // Insert URL
            $output = str_replace('urlString', $display_url, $output);

            // Output
            echo($output);
        }
    }else{

        // Format No Results Output
        $output = str_replace('urlString', 'javascript:void(0);', $html);
        $output = str_replace('nameString', '<b>No Results Found.</b>', $output);
        $output = str_replace('functionString', 'Sorry :(', $output);

        // Output
        echo($output);
    }
}


/*
// Build Function List (Insert All Functions Into DB - From PHP)

// Compile Functions Array
$functions = get_defined_functions();
$functions = $functions['internal'];

// Loop, Format and Insert
foreach ($functions as $function) {
    $function_name = str_replace("_", " ", $function);
    $function_name = ucwords($function_name);

    $query = '';
    $query = 'INSERT INTO search SET id = "", function = "'.$function.'", name = "'.$function_name.'"';

    $tutorial_db->query($query);
}
*/
?>

Please help me:

Answer 1

You have to check what mysqli->query methods return before using it.

If there is an error in your SQL query, the query methods should return FALSE and in this case you can ask myslqi what is the error with the error property.

Your code should be like this :

$result = $tutorial_db->query($query);
if($result === FALSE) {
    echo $tutorial_db->error;
    // or do whatever you have to do to fix or log the issue.
}
else {
    while($results = $result->fetch_array()) {
        $result_array[] = $results;
    }
}