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配置
babel 依赖包
"devDependencies": {
"@babel/cli": "^7.11.6",
"@babel/core": "^7.11.6",
"@babel/preset-env": "^7.11.5",
"@babel/plugin-proposal-decorators": "^7.10.5",
"@babel/plugin-proposal-class-properties": "^7.10.4"
}
babel.config
// .babelrc
{
"presets":["@babel/preset-env"],
"plugins": [["@babel/plugin-proposal-decorators", { "legacy": true}],
["@babel/plugin-proposal-class-properties", { "loose" : true}]
]
}
编译文件
"scripts": {"start": "npx babel app.js -o index.js -w"}
类装璜器
新增办法
@flag
class Animal {constructor(name) {this.name = name;}
sayHi() {console.log(this.getName()+"say:'hi'")
}
}
function flag(constructor) {constructor.prototype.getName = function(){return this.name}
}
let monkey = new Animal("monkey");
monkey.sayHi();
传参
@flag({specie:"mammal"})
class Animal {constructor(name) {this.name = name;}
sayHi() {console.log(this.getName()+"say:'hi'")
}
}
function flag(params) {console.log(params);
return (constructor)=>{constructor.prototype.getName = function(){return this.name}
}
}
办法装璜器
@flag
class Animal {constructor(name) {this.name = name;}
@before
sayHi() {console.log(this.getName()+"say:'hi'")
}
}
function flag(constructor) {constructor.prototype.getName = function () {return this.name}
}
function before(target,property,descripot){
let oldMthod = descripot.value;
descripot.value = function(){console.log("before exect");
oldMthod.call(this, ...arguments);
}
}
let monkey = new Animal("monkey");
monkey.sayHi();
正文完
