JavaScript handler.construct()用法及代碼示例

construct:function(target, argumentsList, newTarget)

var B= function(text) {
  this.text = text;
};
var Button1 = new Proxy(B, {
  construct:function(target, parameters) {
document.writeln('Java Script');

    var button= Object.create(target.prototype);
    target.apply(button, parameters);
    return button;
  }
});

var button = new Button1('proxy Constructor');
document.writeln(button.text);

Java Script proxy Constructor

var pro = new Proxy(function()
                    {}, {
  construct:function(objTarget, args, oldConstructor) {
     return { Value:args[0] + " to anybody" }	
  }
})

document.write(JSON.stringify(new pro("Hello "), null, ' '))

{ "Value":"Hello to anybody" } 

function M(val) {
  this.val = val;
}

const N = {
  construct(target, args) {
  document.writeln('Constructor called');
  return new target(...args);
  }
};
const proxy= new Proxy(M, N)
document.writeln(new proxy('Proxi').val);

Constructor called Proxi