當在php中使用bind_param（）時出現錯誤

Question

我在使用bind_param()時不斷收到跟隨錯誤，並試圖用一切方法解決它，但似乎沒有任何效果。

Warning: mysqli_stmt::bind_param(): Number of elements in type definition string doesn't match number of bind variables

這裏是我的代碼

$output = ''; 
$output2 = ''; 
$output3 = ''; 

    if(isset($_POST['search'])) { 
    $search = $_POST['search']; 
    $search = preg_replace("#[^0-9a-z]i#","", $search); 



    if ($stmt = $db->prepare("SELECT * FROM Users WHERE name LIKE '%$search%'")){ 
    $stmt->bind_param("s", $search); 
    $count = $stmt->num_rows(); 
    $stmt->execute(); 


    if($count == 0){ 
     $output = "There was no search results!"; 

    }else{ 

     while ($rows = $stmt->num_rows) { 

     $name = $row ['name']; 
     $location = $row ['location']; 
     $gender = $row ['gender']; 
     $date_of_birth = $row ['date_of_birth']; 
     $picture = $row['url']; 



     $output .='<form action="header.php" method="post"><div class="row"><div class="col-sm-3">'.$name.'<br>'.$location.'<br>'.$gender.'<br>'.$date_of_birth.'</div>'; 

     $output2 = '<div class="col-sm-3"><img src="upload/'.$picture.'"width="180" height="144" /></div></div>'; 

     $output3 = '<input id="add_friend" name= "addfriend" type="submit" value="Add As Friend" /></form>'; 

     } 

    } 
    } 

Answer 1

您需要將值綁定到查詢字符串的佔位符?。然後你需要看看你傳遞給bind_param()的參數 - 第一個參數應該是變量的類型 - 在這種情況下，$search只是一個字符串，所以第一個參數應該是s。

此外，您應該注意，$stmt->num_rows是屬性，而不是一種方法。除非先存儲結果，否則此屬性可能不準確（也就是說，它可能會在取得結果之前顯示零行），首先使用$stmt->store_result()。在執行之後，這兩者都需要到達。

然後你需要使用bind_param()綁定結果。這意味着綁定查詢選擇的每一列。因此，最好選擇你正在尋找的特定列，而不是做SELECT *。當您現在獲取時，它應該是提供給while的單個參數，而不將其分配給變量。

$search = "%$search%"; 
if ($stmt = $db->prepare("SELECT name, location, gender, date_of_birth, url FROM Users WHERE name LIKE ?")){ 
    $stmt->bind_param("s", $search); 
    $stmt->execute(); 
    $stmt->bind_result($name, $location, $gender, $date_of_birth, $picture); 
    $stmt->store_result(); 
    $count = $stmt->num_rows; 

    if ($count == 0) { 
     $output = "There was no search results!"; 
    } else { 
     while ($stmt->fetch()) { 
      // You can use $name, $location, $gender, $date_of_birth, $picture here 
      $output .='<form action="header.php" method="post"><div class="row"><div class="col-sm-3">'.$name.'<br>'.$location.'<br>'.$gender.'<br>'.$date_of_birth.'</div>'; 

      $output2 = '<div class="col-sm-3"><img src="upload/'.$picture.'"width="180" height="144" /></div></div>'; 

      $output3 = '<input id="add_friend" name= "addfriend" type="submit" value="Add As Friend" /></form>'; 
     } 
    } 
} 

• PHP.net on mysqli_stmt::bind_param()
• PHP.net on mysqli_stmt::bind_result()
• PHP.net on mysqli_stmt::num_rows
• PHP.net on mysqli_stmt::store_result()