如何为HttpWebRequest设置HttpRequestHeader?

Mr.*_*ble 6 c# httpwebrequest

我正在尝试为HttpWebRequest设置HttpRequestHeader,如下所示:

new HttpWebRequest().Headers.Add(HttpRequestHeader.UserAgent, "Mozilla/4.0");
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但我得到一个例外:System.ArgumentException: This header must be modified using the appropriate property.

我该如何设置标题?

Sim*_*der 9

UserAgent是一个属性.所以设置如下:

HttpWebRequest request = new HttpWebRequest();
request.UserAgent = "Mozilla/4.0";
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