由网友(倾你、一世柔情づ)分享简介：我正在开发 C#XAML metro-ui 应用程序.我想调用一些服务并为此使用 HttpWebRequest .HttpWebRequest 的先前实现包含 ContentLength 和 UserAgent 属性.但是 WinRT 的实现没有它.我尝试使用此 post 中描述的方法.它适用于 UserAgent，但...

我正在开发 C#XAML metro-ui 应用程序.我想调用一些服务并为此使用 HttpWebRequest .HttpWebRequest 的先前实现包含 ContentLength 和 UserAgent 属性.但是 WinRT 的实现没有它.我尝试使用此 post 中描述的方法.它适用于 UserAgent，但不适用于 ContentLength.我试图设置 Headers

I developing C#XAML metro-ui application. I want to call some service and going to use HttpWebRequest for this. Previous realization of HttpWebRequest contains ContentLength and UserAgent properties. But realization for WinRT doesn't have it. I tried to use the approach described in this post. It works for UserAgent but not for ContentLength. I've tried to set Headers

request.Headers["Content-length"] = Length;
request.Headers["User-agent"] = UserAgent;

但收到异常必须使用适当的属性或方法修改'Content-length'标头."

But received the exception "The 'Content-length' header must be modified using the appropriate property or method."

Hot 是否可以在WinRT中实现的HttpWebRequest中设置Headers?

Hot is it possible to set Headers in HttpWebRequest realized in WinRT?

推荐答案

HttpWebRequest 在 WinRT 下处于半弃用状态.以前可以在早期 .NET 平台上修改的某些标头值现在无法再用它进行修改.

HttpWebRequest has a semi-deprecated status under WinRT. Some header values that could previously be modified on earlier .NET platforms can no longer cannot be modified with it.

似乎 HttpClient 是 HttpWebRequest 的新改进替代品，具有简单的 API 和完整的异步支持.

It seems that HttpClient is the new and improved replacement for HttpWebRequest with a simple API and full async support.

由于您要指定 Content-Length，我假设您正在尝试向服务器发布或放置某些内容.在这种情况下，您需要酌情使用 PostAsync() 或 PutAsync().

Since you want to specify Content-Length, I assume you're trying to POST or PUT something to the server. In that case, you will want to use PostAsync() or PutAsync() as appropriate.

    var req = new HttpClient();
    req.DefaultRequestHeaders.Add("User-agent", UserAgent);
    req.DefaultRequestHeaders.Add("Content-length", Length);
    return await req.PostAsync(RequestURL, Body);

您可能实际上不需要指定 Content-length 标头，因为这些方法会根据 Body 的实际长度自动包含它，但您可以尝试任何一种方式.

You probably don't really need to specify the Content-length header, since it will be automatically included by those methods based on the actual length of the Body, but you can try it either way.