<a download="data.csv">

var getData= "\ufeff" + "填写数据abc";
var blob = new Blob([getData], {
     type: 'text/csv,charset=UTF-8'
    });
    document.querySelector("#getData").href = URL.createObjectURL(blob);

• 类式继承
• 构造函数继承
• 组合继承
• 寄生组合式继承
• extends继承