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HomeBackend DevelopmentPHP Tutorial看看还有谁会犯这两个错误????

第一个JS问题

<input id="bid" value="5000"><input id="reserve_price" value="750.00"><script>	$$=function(id){	return document.getElementById(id);}var error='';if($$("bid").value.replace(/^\s+/,"").replace(/\s+$/,"")<$$("reserve_price").value){			error+="Your bid must be equal to or higher than the reserve price\n";		}		alert($$("bid").value.replace(/^\s+/,"").replace(/\s+$/,""));		alert($$("reserve_price").value);		alert(error);</script>


你们认为这写法对吗?认为对的请运行程序看看,娃哈哈。。

第二个数据库问题。
数据表名称product
id  int(4)
name  varchar(20);
price  text

有2条记录
id   name    price
1    电视机  750.00
2    空调    5000

按价格高低排序出来
写sql语句
select * from product order by price desc

认为对的请运行看看,


回复讨论(解决方案)

一直很关注楼主。

首先,我不会把价格字段用text存储,因此不会有这个错误。

一直很关注楼主。 关注我干嘛

第一个JS问题

<input id="bid" value="5000"><input id="reserve_price" value="750.00"><script>	$$=function(id){	return document.getElementById(id);}var error='';if($$("bid").value.replace(/^\s+/,"").replace(/\s+$/,"")<$$("reserve_price").value){			error+="Your bid must be equal to or higher than the reserve price\n";		}		alert($$("bid").value.replace(/^\s+/,"").replace(/\s+$/,""));		alert($$("reserve_price").value);		alert(error);</script>


你们认为这写法对吗?认为对的请运行程序看看,娃哈哈。。

第二个数据库问题。
数据表名称product
id  int(4)
name  varchar(20);
price  text

有2条记录
id   name    price
1    电视机  750.00
2    空调    5000

按价格高低排序出来
写sql语句
select * from product order by price desc

认为对的请运行看看,

第一个明明是价格还要走正则替换,而且价格比较好的习惯就是变成数字对比。
我觉得不是“谁会犯这两个错误”,而是“谁会写出这种代码”。

第一个是文本框里输入的,
比如我可以输入5000       ,后面这么多空格

第二个价格是固定的


第一个JS问题

<input id="bid" value="5000"><input id="reserve_price" value="750.00"><script>	$$=function(id){	return document.getElementById(id);}var error='';if($$("bid").value.replace(/^\s+/,"").replace(/\s+$/,"")<$$("reserve_price").value){			error+="Your bid must be equal to or higher than the reserve price\n";		}		alert($$("bid").value.replace(/^\s+/,"").replace(/\s+$/,""));		alert($$("reserve_price").value);		alert(error);</script>


你们认为这写法对吗?认为对的请运行程序看看,娃哈哈。。

第二个数据库问题。
数据表名称product
id  int(4)
name  varchar(20);
price  text

有2条记录
id   name    price
1    电视机  750.00
2    空调    5000

按价格高低排序出来
写sql语句
select * from product order by price desc

认为对的请运行看看,

第一个明明是价格还要走正则替换,而且价格比较好的习惯就是变成数字对比。
我觉得不是“谁会犯这两个错误”,而是“谁会写出这种代码”。

if($$("bid").value.replace(/^\s+/,"").replace(/\s+$/,"") 应为
if(parseFloat($$("bid").value)
select * from product order by price desc
应为
select * from product order by price+0 desc
或将 price 改为 DECIMAL 类型

再有 .replace(/^\s+/,"").replace(/\s+$/,"") 的写法也太怪异了
.replace(/^\s+|\s+$/g,"")

再有 .replace(/^\s+/,"").replace(/\s+$/,"") 的写法也太怪异了
.replace(/^\s+|\s+$/g,"")
也对 对正则不自信的表现 以前在网上找的,然后就一直这样用了

首先,我不会把价格字段用text存储,因此不会有这个错误。
这个错是由于使用了一些cms系统,后台建立数据字段,由于没有特别设置,默认text,so……


一直很关注楼主。 关注我干嘛
你的:YouYaX开源论坛



一直很关注楼主。 关注我干嘛
你的:YouYaX开源论坛
咦,csdn改版了?突然觉得csdn的引用效果有点在模仿我的设计,
以前不是这样的。

呵呵,

不可能犯这样的错误。price怎么可能是文本?

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