HttpClient: Impossible to send "Accept: a;charset=b" #21131
Description
I want to make a http request with a header "Accept" with value "a;charset=b".
It is impossible to do that with HttpClient.
using (var client = new HttpClient())
{
client.DefaultRequestHeaders.TryAddWithoutValidation("Accept", "a;charset=b");
// ...
}This will generate a request with header "Accept" with value "a; charset=b".
Yes, this extra space is obviously valid, but the original value was also valid. And there are APIs out there that won't work with the extra space.
The only way to make it work is to hack it with reflection:
client.DefaultRequestHeaders.TryAddWithoutValidation("Accept", "foo");
foreach (var v in client.DefaultRequestHeaders.Accept)
{
if (v.MediaType.Contains("foo"))
{
var field = v.GetType().GetTypeInfo().BaseType.GetField("_mediaType", BindingFlags.NonPublic | BindingFlags.Instance);
field.SetValue(v, "a;charset=b"); // avoid MediaType's validation
v.CharSet = "";
}
}Sugestion:
client.DefaultRequestHeaders.AddHeaderAndDontMessWithItDontChangeItDontParseItIWantTotalControlThankYouVeryMuch("Whatever header I want", "Whatever value I want");