测试应用时Chrome正常但IE报SCRIPT7002: XMLHttpRequest错误求助

Hey there, let's dig into that IE-specific XMLHttpRequest error you're facing—this is a pretty common issue with older IE versions, so let's walk through the most likely causes and fixes step by step:

1. 跨域请求（CORS）兼容性问题 #

IE handles cross-origin requests way differently than modern browsers like Chrome. Here's what to check:

• For IE10/11: Make sure your server sends proper CORS headers (like Access-Control-Allow-Origin). Note that IE doesn't allow the wildcard * if your request includes credentials (cookies, for example)—you need to specify the exact origin instead.
• For IE9 and earlier: The standard XMLHttpRequest doesn't support CORS at all. You'll need to use XDomainRequest instead, which has a different API (no onreadystatechange, just onload/onerror handlers) and stricter limitations (no custom headers, only GET/POST methods).

2. Local file protocol (file://) restrictions #

If you're opening your app directly from the filesystem (using file://), IE's default security settings block XHR requests to both local and remote resources. Fixes here:

• Deploy your app to a local web server (like IIS, Apache, or even a simple tool like http-server) and access it via http://localhost instead.
• As a temporary test workaround: Go to Internet Options → Security → Local Intranet → Custom Level, find "Access data sources across domains" under the "Miscellaneous" section, and set it to "Enable". (Don't leave this on permanently—it's a security risk.)

3. Security zone conflicts #

IE categorizes sites into security zones (Internet, Local Intranet, Trusted Sites). If your app's page and the target API are in different zones, IE might block the request:

• Add the API's domain to the same security zone as your app, or add it to the Trusted Sites list.
• Check if "Protected Mode" is enabled for the zone—if it is, cross-zone requests often get blocked. You can toggle this off temporarily for testing (again, not recommended for regular use).

4. Unsupported request headers or methods #

IE's XHR has strict rules around certain request details:

• Custom headers (other than standard ones like Authorization) might trigger a preflight OPTIONS request—make sure your server handles these correctly.
• IE9 and earlier don't support HTTP methods like PUT or DELETE for cross-origin requests. If you're using these, switch to POST for IE, or add server-side support to handle the method override.
• Avoid using Content-Type: application/json in IE9 XHR requests—use application/x-www-form-urlencoded instead, since IE9 has trouble parsing JSON payloads with the standard XHR object.

5. Third-party plugin or security software interference #

Sometimes IE add-ons (like ad blockers, antivirus tools, or privacy extensions) can intercept and block XHR requests. Try:

• Closing all IE plugins and restarting the browser.
• Launching IE in "No Add-ons" mode (go to Start → All Programs → Accessories → System Tools → Internet Explorer (No Add-ons)) to test if the issue goes away.

内容的提问来源于stack exchange，提问作者Ramana