You've already seen how to check for a 404 error when a URL doesn't exist.

您已经看到了当 URL 不存在时应该如何检查 404 错误。

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To check if the URL has been stored in the cookie store, use the following code to print out each cookie in the store.

为了检查缓存存储中是否存储了URL，您可以使用接下来的代码来打印存储中的每一个缓存。

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If this turns into a common problem — perhaps a certain script or servlet is offline quite a bit — you might want to check for the URL before making a full GET or POST request.

如果这变成一个常见的问题——可能是缺少了一个特定的脚本或servlet——那么您就可能会希望在生成完整的GET或POST请求之前来检查这个URL。

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The company warned users to double-check the URL to ensure they were visiting the correct site.

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