为vue添加公用方法，vue添加通用方法

common.js

var common =function() {
    return{
        f1:function(){
                    console.log("this is common f1().");
            },
        f2:function(){
                    console.log(" out vist f222222().");
            },
        // 小写转大写
        toUppercase:function(o,parName){
                        if(o && o[parName]){
                            o[parName] = o[parName].toUpperCase();
                        }
                    }
    }}();
if(typeof(Vue)=="function")Vue.prototype.common=common;

html页

<html>
<head>
<meta charset="UTF-8">
<script src="https://vuejs.org/js/vue.min.js"></script>
<script src="common.js"></script>
</head>
<body>
<div id="app">
<br>username:<input type="text" @keyup="common.toUppercase(v1,'username')" v-model="username" >
{{username}}
<br>userobj:<input type="text" @keyup="common.toUppercase(userobj,'usernameEN')" v-model="userobj.usernameEN" >
</div>

</body>
</html>
<script>
var v1=new Vue({
  el: '#app',
  data: {
    username:"",
    userobj:{usernameEN:""}
    },
  created:function(){
        this.common.f1();
  }
    ,methods:{
        testf2:function(){
        //this.common.f2();
        }
    }
})


//在vue外面也可以调用
common.f1();
common.f2();
</script>