获取iframe 里面的内容
let iframe1 = document.querySelector('iframe');
//let iframe1 = window.frames["iframe的name值"]
let html1 = .contentWindow.document;//拿到iframe里的document
获取iframe 父窗口
let parentWindow = window.parent.document;//父窗口的文档
let iframe1 = document.querySelector('iframe');
//let iframe1 = window.frames["iframe的name值"]
let html1 = .contentWindow.document;//拿到iframe里的document
let parentWindow = window.parent.document;//父窗口的文档