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Detailed explanation of the effect of the secondary linkage menu implemented by php mysql, mysql linkage_PHP tutorial
Detailed explanation of the effect of the secondary linkage menu implemented by php mysql, mysql linkage_PHP tutorial
Jul 12, 2016 am 08:52 AM
Detailed explanation of the secondary linkage menu effect implemented by php mysql, mysql linkage
This article describes the secondary linkage menu effect implemented by php mysql. Share it with everyone for your reference, the details are as follows:
<!--php+mysql二級聯(lián)動-->
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>生成學(xué)院專業(yè)級聯(lián)下拉菜單測試 </title>
</head>
<body>
<? //
/***********************************************
** 功 能： php+mysql+javascript實現(xiàn)學(xué)院專業(yè)二級級聯(lián)下拉框
** 數(shù)據(jù)庫：數(shù)據(jù)庫名（ dms）、數(shù)據(jù)表（ colleges、 majors）
** 表 colleges中字段： college_id（ id編號）、 name（學(xué)院名）
** 表 majors中的字段： major_id（ id編號）、 college_id（學(xué)院 ID）、 name（學(xué)院名）
** version 1.0
** 作 者： wu yaowen
***********************************************/
//****************** 連接選擇數(shù)據(jù)庫 ***************
$link = mysql_connect("localhost", "root", "123456")
or die("Could not connect : " . mysql_error());
mysql_select_db("dms") or die("Could not select database");
//******************提取學(xué)院信息 ******************
$queryCol = "select * from colleges order by college_id ";
mysql_query("SET NAMES 'gb2312'");
$result1 = mysql_query($queryCol) or die("Query failed : " . mysql_error());
$colleges = array();
while( $row1 = mysql_fetch_array($result1) )
{
$colleges[] = $row1;
}
//print_r ($forum_data);
mysql_free_result($result1);
//**************獲取專業(yè)信息 **************
$queryMaj = "select * from majors order by college_id desc";
mysql_query("SET NAMES 'gb2312'");
if( !($result2 = mysql_query($queryMaj)) )
{
die('Could not query t_city list');
}
$majors = array();
while( $row2 = mysql_fetch_array($result2) )
{
$majors[] = $row2;
}
mysql_free_result($result2);
?>
<!--************ JavaScript處理 college-onChange *************-->
<script language = "JavaScript">
var majorCount; // 存儲專業(yè)記錄條數(shù)
// form_majors[] 儲存專業(yè) major數(shù)據(jù)，如 {(1,1,電子商務(wù) ),(4,1,計算機科學(xué) ),(3,2,古典文學(xué) )}
form_majors = new Array();
<?php
$num2 = count($majors); // $num2 獲取專業(yè)表中記錄的個數(shù)
?>
majorCount = <?php echo $num2;?>;
<?
for($j=0;$j<$num2;$j++) // 從 0開始取出上面 majors[]中存儲的專業(yè)數(shù)據(jù)填充數(shù)組
{
?>
form_majors[<?echo $j;?>] = new Array("<?echo $majors[$j]['major_id'];?>","<?echo $majors[$j]['college_id'];?>","<?echo $majors[$j]['name'];?>");
<?php
}
?>
function changeCollege(college_id)
{
document.stu_add_form.major.length = 0;
var id=id;
var j;
document.stu_add_form.major.options[0] = new Option('==選擇專業(yè) ==',''); // label的 value為空 ' '
for (j=0;j < majorCount; j++) // 從 0開始判斷
{
if (form_majors[j][1] == college_id) // if college_id等于選擇的學(xué)院的 id
{
document.stu_add_form.major.options[document.stu_add_form.major.length] = new Option(form_majors[j][2], form_majors[j][0]);
}
}
}
</script>
<!--********************頁面表單 *************************-->
<form name="stu_add_form" method="post">
選擇： <select name="college" onChange="changeCollege(document.stu_add_form.college.options[document.stu_add_form.college.selectedIndex].value)" size="1">
<option selected>==請選擇學(xué)院 ==</option>
<?php
$num = count($colleges);
for($i=0;$i<$num;$i++)
{
?>
<option value="<?echo $colleges[$i]['college_id'];?>"><?echo $colleges[$i]['name'];?></option>
<?
}
?>
</select>
<select name="major">
<option selected value="">==選擇專業(yè) ==</option>
</select>
</form>
</body>
</html>
sql statement:
-- -- 表的結(jié)構(gòu) `colleges` -- CREATE TABLE IF NOT EXISTS `colleges` ( `college_id` int(8) NOT NULL auto_increment COMMENT '學(xué)院編號自動增加', `name` varchar(40) NOT NULL COMMENT '學(xué)院名稱', PRIMARY KEY (`college_id`), UNIQUE KEY `name` (`name`) ) ENGINE=InnoDB DEFAULT CHARSET=gb2312 AUTO_INCREMENT=7 ; -- -- 導(dǎo)出表中的數(shù)據(jù) `colleges` -- INSERT INTO `colleges` (`college_id`, `name`) VALUES (4, '化學(xué)與化工學(xué)院'), (1, '計算機與信息科學(xué)學(xué)院'), (6, '美術(shù)學(xué)院'), (2, '文學(xué)院'), (5, '音樂學(xué)院'), (3, '政治與公共管理學(xué)院'); -- -- 表的結(jié)構(gòu) `majors` -- CREATE TABLE IF NOT EXISTS `majors` ( `major_id` int(8) NOT NULL auto_increment COMMENT '專業(yè)號，自動增加', `name` varchar(40) NOT NULL COMMENT '專業(yè)名', `college_id` int(8) default NULL COMMENT '所在學(xué)院', `counsellor_id` int(10) default NULL COMMENT '輔導(dǎo)員', PRIMARY KEY (`major_id`), UNIQUE KEY `college_id` (`college_id`,`counsellor_id`) ) ENGINE=InnoDB DEFAULT CHARSET=gb2312 AUTO_INCREMENT=8 ; -- -- 導(dǎo)出表中的數(shù)據(jù) `majors` -- INSERT INTO `majors` (`major_id`, `name`, `college_id`, `counsellor_id`) VALUES (1, '電子商務(wù)', 1, 1), (2, '音樂視唱', 5, 1), (3, '古典文學(xué)', 2, 1), (4, '計算機科學(xué)', 1, NULL), (5, '自動化', 1, NULL), (6, '現(xiàn)代文學(xué)', 2, NULL), (7, '新聞寫作', 2, NULL);
Readers who are interested in more PHP-related content can check out the special topics of this site: "Summary of PHP database operation skills based on pdo", "PHP MongoDB database operation skills collection", "php object-oriented programming introductory tutorial", "php Summary of String Usage", "Introduction Tutorial on PHP MySQL Database Operation" and "Summary of PHP Common Database Operation Skills"
I hope this article will be helpful to everyone in PHP programming.
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