Question

这是一个简单的;假设我有一个从数据库中提取值的脚本，每次用户单击一个按钮时，该值减少一个计数，如何防止该值降低到零以下，

 if(count>0){
           $.post(sessionStorage.server, { count:count ,request:"counter",user:sessionStorage.sname });
        }

if(count==0){
            alert("Your value is now zero");
            sessionStorage.clear();
            sessionStorage.msg="Logged off, ran out of clicks";
            window.location.href = "../index.html";
        }

Answer 1

试试这个

if(count==0){
            alert("Your value is now zero");
            sessionStorage.clear();
            sessionStorage.msg="Logged off, ran out of clicks";
            window.location.href = "../index.html";
        }
else if(count>0){
           $.post(sessionStorage.server, { count:count ,request:"counter",user:sessionStorage.sname });
        }

Answer 2

替换这个

if(count==0){

这一个

if(count<=0){

Answer 3

原始代码看起来不错，只是一些建议

1.add else将改善js性能

if(count>0){
       $.post(sessionStorage.server, { count:count ,request:"counter",user:sessionStorage.sname });
}
else if(count==0){
        alert("Your value is now zero");
        sessionStorage.clear();
        sessionStorage.msg="Logged off, ran out of clicks";
        window.location.href = "../index.html";
}

2.检查服务器端的计数，永远不要相信js验证

jQuery / JavaScript：减去当前值＆＃39;直到＆＃39;零＆＃39;

3 个答案: