Write a proxy class in typescript that can call a given iframe using postmessage in its handler and passes all the function arguments as data in the message
  Sure! Here's an example of a proxy class in TypeScript that can call a given iframe using `postMessage()` and pass all function arguments as data in the message:
```typescript
class Proxy {
  iframe: HTMLIFrameElement;

  constructor(iframe: HTMLIFrameElement) {
    this.iframe = iframe;
  }

  callFunction(funcName: string,...args: any[]) {
    const message = { funcName, args };
    this.iframe.contentWindow.postMessage(message, '*');
  }
}
```
Here's how you can use the `Proxy` class:
```typescript
const iframe = document.getElementById('myIframe');
const proxy = new Proxy(iframe);

// Call a function in the iframe with arguments
proxy.callFunction('myFunction', 1, 2, 3);
```
In this example, the `callFunction()` method of the `Proxy` class takes a string `funcName` and an array of arguments `args`. It creates a message object with the `funcName` and `args` data, and then posts the message to the iframe's `contentWindow` using `postMessage()`.

The `contentWindow` of the iframe will receive the message and execute the function with the passed arguments.

Note that the `post
 Sure! Here's an example of a proxy class in TypeScript that uses `postMessage` to call a function on an iframe and passes all the function arguments as data in the message.
```typescript
interface IframeHandler {
  (...args: any[]): void;
}

class IframeProxy {
  private iframe: HTMLIFrameElement;
  private handler: IframeHandler;

  constructor(iframe: HTMLIFrameElement, handler: IframeHandler) {
    this.iframe = iframe;
    this.handler = handler;

    window.addEventListener('message', this.messageHandler);
  }

  private messageHandler = (event: MessageEvent) => {
    if (event.source === this.iframe.contentWindow && event.data === 'executeHandler') {
      this.handler(...event.args as any[]);
    }
  }

  public callHandler(...args: any[]) {
    this.iframe.contentWindow.postMessage('executeHandler', '*', args);
  }
}
```
Here's how you can use the `IframeProxy` class:

1. First, create an iframe element in your HTML:
```html
<iframe id="myIframe" src="ifr