问题描述:
用PHP向MySql数据库中修改数据,实现增删改(数据库能正确连接) 经测试,代码只能对数字进行正常的增删改操作,非数字操作无效 但要在课程名称中输入中文,应该如果修改呢? 存在问题的代码主要是: ,$kkxq,$xs,$xf)"
alert('修改信息成功');"
alert('添加信息成功');"
alert('删除信息成功');"
(都是猜的) 由于只对数字有效,故推测传进数据库的数据类型存在问题。 但通过 var_dump($kcm) 得到数据类型是 string 类型。 那么要向数据库传入字符串变量怎么做? 经测试: 可行办法是,给该行代码中的字符串变量加单引号: '$kcm',$kkxq,$xs,$xf)"
但思考到,PHP中双引号才解析变量,所以就有点混乱了,故百度了一下。 值得一看:http://www.jb51.net/article/21035.htm 从这个链接中,弄懂了一些问题。总结如下:
1、简单概括:双引号中的变量可以解析,单引号就是绝对的字符串。单引号、双引号必须成对使用, 2、单引号中的 “\” 反斜杠会被直接输出,双引号中的反斜杠才会被解析为转义字符。 、PHP复杂的变量用花括号括起来,语法分析器就能正确分析。如: 、在插入数据库的SQL语句是采用单引号来定义字符串。 如果要将一个含有单引号的字符串插入数据库,要用转义字符。 addslashes() 函数,该函数的功能:在指定的预定义字符前添加反斜杠。 双引号(")
反斜杠(\)
NULL
http://zh.wikipedia.org/wiki/SQL%E6%B3%A8%E5%85%A5%E6%94%BB%E5%87%BB http://welcome6.blog.163.com/blog/static/189281346201001694237345/

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