c# - How to Post JSON data to a Web API using HttpClient -

i have following code, takes in dynamic object (in case of type file) , using httpclient class tries post webapi controller, issue having controller getting null values on [frombody] parameter.

code

var obj = new         {             f = new file             {                 description = description,                 file64 = convert.tobase64string(filecontent),                 filename = filename,                 versionname = versionname,                 mimetype = mimetype             },         }  var client = new httpclient(signinghandler) {    baseaddress = new uri(baseurl + path) //in case v1/document/checkin/12345 };  client.defaultrequestheaders.accept.clear(); client.defaultrequestheaders.accept.add(new mediatypewithqualityheadervalue("application/json"));                          httpresponsemessage response; action = uri.escapeuristring(action);  //obj passed this, of type file  var content = new stringcontent(jsonconvert.serializeobject(obj).tostring(),             encoding.utf8, "application/json");  response = client.postasync(action, content)).result; if (response.issuccessstatuscode) {          var responsecontent = response.content;                     string responsestring = responsecontent.readasstringasync().result;     return jsonconvert.deserializeobject<t>(responsestring); } 

controller

[httppost] [route("v1/document/checkin/{id:int}")] public void checkin_v1(int id, [frombody] file f) {         //do stuff - f has null on of properties } 

model

public class file {     public string filename { get; set; }     public string versionname { get; set; }     public string description { get; set; }     public string mimetype { get; set; }     public byte[] bytes { get; set;}     public string file64 { get; set; } } 

the model shared on both webapi , client app.

any on why failing appreciated, been going around in circles while now.

your obj right @ start isn't needed. nesting f inside object.

var obj = new     {         f = new file         {             description = description,             file64 = convert.tobase64string(filecontent),             filename = filename,             versionname = versionname,             mimetype = mimetype         },     } 

change to

var f = new file {     description = description,     file64 = convert.tobase64string(filecontent),     filename = filename,     versionname = versionname,     mimetype = mimetype }; 

then serialize f.