c# httpcontent - 添加 Header If-Match 错误

c# httpcontent - add Header If-Match errors

正在添加新的 header "If-Match"

 using (HttpContent content = new StringContent(serializedObject))
        {
            content.Headers.Remove("Content-Type");
            content.Headers.Add("Content-Type", "application/json");
            content.Headers.Remove("If-Match");
            content.Headers.Add("If-Match", "XXXXXXXXXX");
        }

抛出:

Misused header name. Make sure request headers are used with HttpRequestMessage, response headers with HttpResponseMessage, and content headers with HttpContent objects.

我可以添加任何其他 header 没问题

已编辑:

using(var request = new HttpRequestMessage(HttpMethod.Put, new Uri(url))) {
    request.Headers.Remove("If-Match");
    request.Headers.TryAddWithoutValidation("If-Match", "XXXXXXXXXX");
    using (HttpContent content = new StringContent(serializedObject))
    {
        content.Headers.Remove("Content-Type");
        content.Headers.Add("Content-Type", "application/json");
    }
    // ...
}