将页面的JSON数据保存到本地:
var content = JSON.stringify(json对象);
var eleLink = document.createElement('a');
eleLink.download = "info.json";
eleLink.style.display = 'none';
// 字符内容转变成blob地址
var blob = new Blob([content]);
eleLink.href = URL.createObjectURL(blob);
// 触发点击
document.body.appendChild(eleLink);
eleLink.click();
// 然后移除
document.body.removeChild(eleLink);