c# - List<T> passed to controller sends empty items -

a partialview contains model foo list<bar>. each bar item contains 2 properties, bara (string) , barb (decimal).
trying render chart in partial view, work need call action on same controller , pass result <img /> element. render chart, need collections of bara , barb format data.
i'm trying this:

controller

public void generatechart(list<bar> model) {     var chart = new system.web.helpers.chart(400, 200)     .addtitle("title")     .addseries(         name : "name",         xvalue : model.select(m => m.bara).toarray(),         yvalues : model.select(m => m.barb).toarray())     .write(); } 

partial view

routevaluedictionary rvd = new routevaluedictionary(); (int = 0; < model.bars.count; ++i) { rvd.add("model[" + + "]", model.bars[i]); }  <img src="@url.action("generatechart", rvd)" /> 

the problem though model object contains 3 items should contain, these null.
tried use viewbag, this:

viewbag.bara = model.bars.select(m => m.bara).toarray(); viewbag.barb = model.bars.select(m => m.barb).toarray(); 

with on controller side

public void generatechart() {     var chart = new system.web.helpers.chart(400, 200)     .addtitle("title")     .addseries(         name : "name",         xvalue : viewbag.bara,         yvalues : viewbag.barb)     .write(); } 

but both arrays null. i've tried few different ideas i'm not able information need.

to triple-check (the data shown fine in view) data correct, changed this:

@{     string[] baras = model.select(m => m.bara).toarray();     decimal[] barbs = model.select(m => m.barb).toarray();     viewbag.baras = baras; // has 3 items expected data     viewbag.barbs = barbs; // works } <img src="@url.action("generatechart")" />  string[] baras = viewbag.baras; // assigns null decimal[] barbs = viewbag.barbs; // assigns null 

passing complex type actions via request technically bloody thing not know if solution fits needs can follow method below;

your action recieve model serialized string , have deserialize model

public actionresult generatechart(string modelasstring) {     list<bar> model = new list<bar>();     model = jsonconvert.deserializeobject<list<bar>>(modelasstring);      var chart = new system.web.helpers.chart(400, 200)     .addtitle("title")     .addseries(         name: "name",         xvalue: model.select(m => m.bara).toarray(),         yvalues: model.select(m => m.barb).toarray())     .getbytes("jpeg");      return file(chart, "image/jpeg"); } 

then need call action via querystring ?modelasstring={jsondata} example url use process data : http://localhost:18681/home/generatechart/?modelasstring=[{%22bara%22:%22baradata%22,%22barb%22:1.1},{%22bara%22:%22baradata2%22,%22barb%22:441.14},{%22bara%22:%22baradata43%22,%22barb%22:44.1}]

you should create <img> urls via serializing model ready on page's action use <img>s.

i have tested dummy data can see output below;

ps: creating dummy data used method below;

public actionresult dummydata() {     list<bar> model = new list<bar>();     model.add(new bar() { bara = "baradata", barb = 1.1m });     model.add(new bar() { bara = "baradata2", barb = 441.14m });     model.add(new bar() { bara = "baradata43", barb = 44.1m });     return json(model, jsonrequestbehavior.allowget); } 

and wonder if more efficient way via request.

hope helps!