php - 如何使用 PHP 在 MySQL 上显示随机数据？

Question

你好，我有这样的表格:

员工

EmployeeID  EmployeeName 
1234        Nayeon     
1235        Jihyo     
1236        Jungyeon     
1237        Dahyun     
1238        Sana       
1239        Mina
1240        Tzuyu
1241        Chaeyeong
1241        Chaeyeong
1242        Momo

我使用了这个源代码:

<?php

mysql_connect("localhost", "root", "1234") or die(mysql_error());
mysql_select_db("databasetransport") or die(mysql_error());

$employees = mysql_query("SELECT * FROM Employee ORDER BY EmployeeID") 
or die(mysql_error());  

$letters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
$position = 0;
$position2 = 0;
$toomany = '';

while($row = mysql_fetch_array( $employees )) {
    echo "<DIV>" . $toomany.substr($letters, $position, 1) . " = " . $row['EmployeeName'] . " </div>";
      $position ++;
    if($position > 25) {
        $position = 0;
        $position2 ++;
        if($position2 > 25) { echo "We need to rethink this idea."; break; }
        $toomany = substr($letters, $position2, 1);
    }
}
?>

显示这些数据:

 A  = Nayeon     
 B  = Jihyo     
 C  = Jungyeon     
 D  = Dahyun     
 E  = Sana       
 F  = Mina
 G  = Tzuyu
 F  = Chaeyeong
 H  = Chaeyeong
 I  = Momo

问题是我想像这样随机数据(来自之前的结果):

C  = Jungyeon 
A  = Nayeon 
H  = Chaeyeong    
B  = Jihyo 
I  = Momo        
F  = Mina
G  = Tzuyu
E  = Sana  
F  = Chaeyeong
D  = Dahyun     

所以我添加这样的代码:

 <?php

mysql_connect("localhost", "root", "1234") or die(mysql_error());
mysql_select_db("databasetransport") or die(mysql_error());

$employees = mysql_query("SELECT * FROM Employee ORDER BY EmployeeID") 
or die(mysql_error());  

$letters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';
$position = 0;
$position2 = 0;
$toomany = '';

while($row = mysql_fetch_array( $employees )) {
    echo "<DIV>" . $toomany.substr($letters, $position, 1) . " = " . $row['EmployeeID'] . " </div>";
      $position ++;
    if($position > 25) {
        $position = 0;
        $position2 ++;
        if($position2 > 25) { echo "We need to rethink this idea."; break; }
        $toomany = substr($letters, $position2, 1);
    }
}


function generateRandomString($length = 10) {
    $characters = $positions;
    $charactersLength = strlen($characters);
    $randomString = '';
    for ($i = 0; $i < $length; $i++) {
        $randomString .= $characters[rand(0, $charactersLength - 1)];
    }
    return $randomString;
}


echo generateRandomString();

?>

但是什么也没发生(笑)你知道问题出在哪里吗？谢谢

Answer 1

只需构建您的数组，然后使用它

http://php.net/manual/en/function.shuffle.php

干杯。

$a = array(
    'A = Nayeon',
    'B = Jihyo',
    'C = Jungyeon',
    'D = Dahyun',
    'E = Sana',
    'F = Mina',
    'G = Tzuyu',
    'F = Chaeyeong',
    'H = Chaeyeong',
    'I = Momo',
 );
 shuffle( $a );
 var_export( $a );

输出:

array (
  0 => 'I = Momo',
  1 => 'E = Sana',
  2 => 'F = Chaeyeong',
  3 => 'F = Mina',
  4 => 'B = Jihyo',
  5 => 'A = Nayeon',
  6 => 'C = Jungyeon',
  7 => 'G = Tzuyu',
  8 => 'D = Dahyun',
  9 => 'H = Chaeyeong',
)

• 顺便说一句，shuffle 不维护数组键，它会修改数组，这意味着 shuffle 的实际返回是一个 bool 值 ( true | false )。
• 但是，它会保留带有指定字母的姓名(如果需要的话)
• 简单快捷
• 可读
• 确保您不会将同一行拉出两次。