Uncaught TypeError: window.showModalDialog is not a function

Uncaught TypeError: window.showModalDialog is not a function错误的原因是谷歌浏览器已经不支持window.showModalDialog方法了。为了解决这个问题，你可以使用兼容谷歌浏览器的方法来自定义一个模态窗口。下面是一个示例代码：

if (!window.showModalDialog) {
  window.showModalDialog = function(url, name, options) {
    if (window.hasOpenWindow) {
      window.newWindow.focus();
    }
    var re = new RegExp(";", "g");
    options = options.replace(re, '","');
    options = '{"' + options.replace(/:/g, '":"') + '"}';
    options = JSON.parse(options);
    var openOptions =
      "width=" +
      parseInt(options.dialogWidth) +
      ",height=" +
      parseInt(options.dialogHeight) +
      ",left=" +
      (window.screen.width - parseInt(options.dialogWidth)) / 2 +
      ",top=" +
      (window.screen.height - 30 - parseInt(options.dialogHeight)) / 2;    window.hasOpenWindow = true;
    window.newWindow = window.open(url, name, openOptions);
  };
}

function showModal() {
  window.showModalDialog(
    "http://www.baidu.com",
    window,
    "dialogWidth:500px;dialogHeight:550px"
  );
}

如果你遇到了Uncaught TypeError: window.showModalDialog is not a function错误，你可以尝试使用以上代码来解决问题。