javascript 基础

ev.stopPropagation();  // 防止事件传递（冒泡或捕获）

ev.preventDefault();  // 阻止元素默认行为

/*
* @desc 生成 min - max 之间的随机整数
* @param min 最小值
* @param max 最大值
* @return num
*/
function rand(min,max){
 return parseInt(Math.random() * (max - min + 1) + min,10);
}

/*
@desc：解析url地址
@param url url地址，如：http://www.baidu.com/a/b/c.jpg?a=b&c=d#id
@return info 解析后的地址，如：
{
 scheme:'http',            #  协议
 host:'www.baidu.com',    #  域名
 port:'',                #  端口
 user:'',                #  验证用户名
 pass:'',                #  验证密码
 path:a/b,                #  路径
 query:'a=b&c=d',        #  查询字符串
 fragment:'id'            #  锚点
}
*/
function parseurl(url){
 var reg = /(?:([A-Za-z]+):)?(\/{0,3})?(?:(.*):(.*)@)?([0-9.\-A-Za-z]+)(?::(\d+))?(?:\/([^?#]*))?(?:\?([^#]*))?(?:#(.*))?/
 var res = reg.exec(url)
 var scheme = (res[1])?res[1]:'http'
 var user = (res[3])?res[3]:''
 var pass = (res[4])?res[4]:''
 var host = (res[5])?res[5]:''
 var port = (res[6])?res[6]:''
 var path = (res[7])?res[7]:''
 var query = (res[8])?res[8]:''
 var fragment = (res[9])?res[9]:''
 var info = {
     scheme:scheme,
     host:host,
     port:port,
     user:user,
     pass:pass,
     path:path,
     query:query,
     fragment:fragment
 }
 return info
}
var ret = parseurl('https://user:pass@www.baidu.com:443/a/b/c.jpg?a=b&c=d#id');
console.log(ret)

1. 表单方式：

   var formdata = new FormData();
   formdata.append('file', $('#file')[0].files[0]);

2. base64 数据流方式：

   var filereader = new FileReader()
   filereader.onload = function(e){
   console.log(e.target.result)
   }
   filereader.readAsDataURL($('#file')[0].files[0])

$(document).click(function (e) {
 if(e.target !== $('#target')[0]){
     $('#target').hide()
 }
})

1. 编码：
   btoa(raw_str)
2. 解码：
   atob(encoded_str)

let p1 = new Promise(function (resolve,reject) {
 setTimeout(function () {
     resolve("p1 done");
 },1000);
}).catch(function (e) {
 console.log("p1 error...",e)
})
let p2 = new Promise(function (resolve,reject) {
 setTimeout(function () {
     // resolve("p2 done");
     reject("p2 error");
 },2000);
}).catch(function (e) {
 console.log(e)
})
Promise.all([p1,p2]).then(function (results) {
 console.log(results)
})