PHP基础有关问题

WBOY
WBOYoriginal
2016-06-13 10:35:36957parcourir

PHP基础问题

PHP code
<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><?php $conn = mysql_connect('localhost', 'root', '');    if(!$conn)    {        echo "数据库连接失败".mysql_error();        exit();    }    echo "数据库连接成功</br>";    $sql = "show databases";  //查找某个库是否存在    print("$sql");    $sql_return = mysql_query($sql);    echo "$sql_return ";    while($row = mysql_fetch_array($sql_return))    {        for($i = 0; $i != count($row); ++$i)        {            printf("%s", $row[0]);            echo "";        }    }    //mysql_select_db('web', $conn);    ?>


输出的结果是这样的:
PHP code
<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->数据库连接成功show databasesResource id #4 information_schemainformation_schemamysqlmysqlperformance_schemaperformance_schematesttestwebweb


????为什么,每个库名都输出了两遍,我也用print_r($row);执行过,结果如下:
PHP code
<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->数据库连接成功show databasesResource id #4 Array ( [0] => information_schema [Database] => information_schema ) Array ( [0] => mysql [Database] => mysql ) Array ( [0] => performance_schema [Database] => performance_schema ) Array ( [0] => test [Database] => test ) Array ( [0] => web [Database] => web )


------解决方案--------------------
mysql_fetch_array()返回的既有数字数组,又有关联数组。你可以换用 mysql_fetch_row()
------解决方案--------------------
http://cn2.php.net/manual/zh/function.mysql-fetch-array.php

你自己看看你这程序写的:

PHP code
        for($i = 0; $i != count($row); ++$i)        {            printf("%s", $row[0]);            echo "";        }<div class="clear">
                 
              
              
        
            </div>
Déclaration:
Le contenu de cet article est volontairement contribué par les internautes et les droits d'auteur appartiennent à l'auteur original. Ce site n'assume aucune responsabilité légale correspondante. Si vous trouvez un contenu suspecté de plagiat ou de contrefaçon, veuillez contacter admin@php.cn