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一些PHP嵌入HTML中语法约定报错的有关问题

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Jun 13, 2016 am 10:34 AM

gtltmysqlquot

一些PHP嵌入HTML中语法约定报错的问题
认真排版了一下HTML，然后慢慢填空，总算把之前发了两个帖子问关于嵌套循环查询的问题解决了。

但是，新问题出现，语法写得不正确，标注出来了，麻烦大家指教一下：

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><?phpinclude_once ('conn.php');$result = mysql_query("SELECT p_class FROM Product group by p_class limit 40"); mysql_data_seek($result, 0);    while ($row=mysql_fetch_row($result))    {      for ($i=0; $i<mysql_num_fields($result); $i++ )      {?>

	more
********

/>//这里报错，说写法不对

//这里报错，说写法不对

多谢！

------解决方案--------------------
老问题前面加 isset 判断

探讨

引用:

Notice: Undefined index: pic
这是一个提示，告诉你数组的一个键 pic 没有定义，也就是没有 $row['pic']。
再直白一点，就是你数据库的 Product 表中没有 pic 这个列

不能啊，我查了，表product中确实有这三个列。

难道不是写法错了？

Notice: Undefined index: ……

------解决方案--------------------
我忘记了 mysql_fetch_row()函数返回的数字数组！
你可以换用 mysql_fetch_assoc(); 他将返回一个关联数组，也就时键名为列名的数组
------解决方案--------------------
养成习惯查手册
一个返回数组一个是返回关联数组...
以后你的问题我还是仔细看看代码才行哈哈哈

探讨

引用:

我忘记了 mysql_fetch_row()函数返回的数字数组！
你可以换用 mysql_fetch_assoc(); 他将返回一个关联数组，也就时键名为列名的数组

牛！谢谢

我把被嵌套的那个mysql_fetch_row改成mysql_fetch_assoc，就搞定了！这两个函数的区别是什么呢？

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