javascript - 如果做到614时 用新上传的资源 代替原来的资源？
在项目中有一些需求 比如用户的头像，我将其命名为 用户id.jpg 这样方便查找。 前端用js 直传时 有时用户只是更新图像 ，这样在再次以此用户id.jpg 上传图像资源时 就会直接失败 。我想要的效果是 直接把原来的图像更新掉 原来的删掉 用上新增的。 请问要如何做到？ 我能想到的方案是 先检查有没有旧的，有的话 先http 让业务服务器删掉，成功删掉返回后 再上传。 这样做很麻烦 而且我也没试成功。 是否有简单的方法呢？
回复内容：
在项目中有一些需求 比如用户的头像，我将其命名为 用户id.jpg 这样方便查找。 前端用js 直传时 有时用户只是更新图像 ，这样在再次以此用户id.jpg 上传图像资源时 就会直接失败 。我想要的效果是 直接把原来的图像更新掉 原来的删掉 用上新增的。 请问要如何做到？ 我能想到的方案是 先检查有没有旧的，有的话 先http 让业务服务器删掉，成功删掉返回后 再上传。 这样做很麻烦 而且我也没试成功。 是否有简单的方法呢？
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