在JavaScript中如何编辑<object>标签的内容值？

Hey there! Let's break down how to tackle this tricky <object> control issue. That classid="ghjkl" tells me this is almost certainly a custom browser plugin or ActiveX control (not a standard HTML element), which is why standard DOM methods like accessing element.value aren't working. Here are actionable steps to try:

1. Inspect the Control's Exposed API #

Custom controls don't follow standard HTML rules—they expose their own properties and methods. The easiest way to uncover these is to use your browser's developer tools:

• Open the console (F12 > Console)
• Run this code to get the element and inspect its full API:

  const objControl = document.getElementById('test');
  console.dir(objControl);
  

• Look through the output for properties like Value, text, content, or methods like getValue(), setText(), setContent(). Many custom controls use camelCase or PascalCase for these (e.g., objControl.Value = "new text" instead of objControl.value).

2. Wait for the Control to Fully Load #

If you're trying to interact with the control before it finishes initializing, you'll get no response. Hook into its onload event to ensure it's ready:

const objControl = document.getElementById('test');
objControl.onload = function() {
  // Try reading/writing values here
  console.log(objControl.Value); // Example: check if this property exists
  objControl.Value = "Your new value";
};

3. Check for Security or Environment Restrictions #

• If this is an ActiveX control: Modern browsers (Chrome, Firefox, Edge Chromium) no longer support ActiveX—you'll need to use Internet Explorer or Edge's IE Compatibility Mode. Also, IE's security settings might block access to the control's properties (check Tools > Internet Options > Security).
• For custom plugins: Ensure the plugin is properly installed and has the necessary permissions to interact with JavaScript.

4. Simulate User Interaction (Last Resort) #

If the control doesn't expose a direct API, you can try simulating user input (though this is less reliable):

• Focus the control first: objControl.focus();
• Create and dispatch keyboard events to input text. For example:

  function sendKey(el, key) {
    const event = new KeyboardEvent('keydown', { key });
    el.dispatchEvent(event);
  }
  
  objControl.focus();
  sendKey(objControl, 'H');
  sendKey(objControl, 'e');
  sendKey(objControl, 'l');
  

Note: This method depends on how the control handles keyboard events, so it might not work for all cases.

Quick Test Snippets to Try #

Start with these simple console commands to rule out common properties:

// Check for common value properties
console.log(objControl.Value);
console.log(objControl.text);
console.log(objControl.content);

// Try common set methods
if (objControl.setValue) objControl.setValue("Test");
if (objControl.setText) objControl.setText("Test");

内容的提问来源于stack exchange，提问作者keloa