


Use the mysql_fetch_row() function to obtain each record in the result set row by row (PHP method 6 for operating MySQL database)
We introduced two types earlier To obtain the data in the result set, today we will introduce to you the third mysql_fetch_row() function to obtain the result set. The usage of this function is similar to the function mentioned above!
In the previous articles "Use the mysql_fetch_array() function to obtain the information in the array result set (PHP method 4 for operating MySQL database)" and "Use the mysql_fetch_object() function to obtain the results Concentrate one row as an object (Method 5 of PHP operating MySQL database) " introduced the mysql_fetch_array() function and mysql_fetch_object() function. In this chapter, we introduce the mysql_fetch_row() function in detail!
The syntax format of the function is as follows:
array mysql_fetch_row(resource result)
mysql_fetch_row() function obtains a row of data from the result set associated with the specified result identifier and returns it as an array. This row is assigned to the array variable $row. The column of each result is stored in an array element. Starting from 0, the first array element is accessed in the form of $row[0] (the same is true when there is only one element). A call to the mysql_fetch_row() function will return the result. The next row in the set will return false if there are no more rows.
Note: The field names returned by this function are case-sensitive!
The following example has the same function as the previous article. The difference is that the following example obtains each record in the result set row by row through the mysql_fetch_row() function. Then use the echo statement to output the book information corresponding to each field from the array result set.
The specific development steps are as follows:
1. The implementation process of creating a project, adding a form, connecting to the database, and selecting the database is the same as in the previous article, so I won’t repeat it here for those who are unclear. Friends, you can check it out. This article is linked to the previous article.
2. Different from the previous article, this example uses the mysql_fetch_row() function to obtain the records in the result set row by row. The core code is as follows:
<?php $sql = mysql_query("select * from tb_book"); $row = mysql_fetch_row($sql); if ($_POST["Submit"]=="查询"){ $txt_book = $_POST["txt_book"]; $sql = mysql_query("select * from tb_book where bookname like '%".trim($txt_book)."%'"); //执行模糊查询 $row = mysql_fetch_row($sql); //逐行获取查询结果,返回值为数组 } ?>
3. Use the if conditional statement to The result set variable $row is judged. If the value is false, then the information you retrieve does not exist. Otherwise, use the do...while loop statement to output the information in the result set in the form of an array. The core code is as follows:
<?php if ($row == false){ echo "<p align='center' style='color: #FF0000;font-size: 12px'>对不起,你要查询的信息不存在</p>"; } ?> <?php do { ?> <table> <tr align="left" bgcolor="#FFFFFF"> <td height="20" align="center"><?php echo $row[0] ?></td> <td height="20" align="center"><?php echo $row[1] ?></td> <td height="20" align="center"><?php echo $row[2] ?></td> <td height="20" align="center"><?php echo $row[3] ?></td> <td height="20" align="center"><?php echo $row[4] ?></td> <td height="20" align="center"><?php echo $row[5] ?></td> </tr> </table> <?php }while ($row = mysql_fetch_row($sql)); ?>
The results of the above example are the same as those of the previous two articles. The pictures are pasted here. Friends can try it locally!
In the next article, we will introduce how to obtain the records in the query result set. For details, please read "Use the mysql_num_rows() function to obtain the number of records in the result set row by row (Method 7 of PHP operating MySQL database)》
The above is the detailed content of Use the mysql_fetch_row() function to obtain each record in the result set row by row (PHP method 6 for operating MySQL database). For more information, please follow other related articles on the PHP Chinese website!

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