[ACCEPTED]-How do I pass a Dictionary as a parameter to an ActionResult method from jQuery/Ajax?-actionresult
At last I figured it out!! Thanks for the 17 suggestions everyone! I finally figured 16 out the best solution is to pass JSON via 15 the Http Post and use a custom ModelBinder 14 to convert the JSON to a Dictionary. One 13 thing I did in my solution is created a 12 JsonDictionary object that inherits from 11 Dictionary so that I can attach the custom 10 ModelBinder to the JsonDictionary type, and 9 it wont cause any conflicts in the future 8 if I use Dictionary as a ActionResult parameter 7 later on for a different purpose than JSON.
Here's 6 the final ActionResult method:
public ActionResult AddItems([Bind(Include="values")] JsonDictionary values)
{
// do something
}
And the jQuery 5 "$.post" call:
$.post("/Controller/AddItems",
{
values: Sys.Serialization.JavaScriptSerializer.serialize(
{
id: 200,
"name": "Chris"
}
)
},
function(data) { },
"json");
Then the JsonDictionaryModelBinder 4 needs to be registered, I added this to 3 the Application_Start method within the 2 Global.asax.cs:
protected void Application_Start()
{
ModelBinders.Binders.Add(typeof(JsonDictionary), new JsonDictionaryModelBinder());
}
And, finally here's the JsonDictionaryModelBinder 1 object and JsonDictionary object I created:
public class JsonDictionary : Dictionary<string, object>
{
public JsonDictionary() { }
public void Add(JsonDictionary jsonDictionary)
{
if (jsonDictionary != null)
{
foreach (var k in jsonDictionary.Keys)
{
this.Add(k, jsonDictionary[k]);
}
}
}
}
public class JsonDictionaryModelBinder : IModelBinder
{
#region IModelBinder Members
public object BindModel(ControllerContext controllerContext, ModelBindingContext bindingContext)
{
if (bindingContext.Model == null) { bindingContext.Model = new JsonDictionary(); }
var model = bindingContext.Model as JsonDictionary;
if (bindingContext.ModelType == typeof(JsonDictionary))
{
// Deserialize each form/querystring item specified in the "includeProperties"
// parameter that was passed to the "UpdateModel" method call
// Check/Add Form Collection
this.addRequestValues(
model,
controllerContext.RequestContext.HttpContext.Request.Form,
controllerContext, bindingContext);
// Check/Add QueryString Collection
this.addRequestValues(
model,
controllerContext.RequestContext.HttpContext.Request.QueryString,
controllerContext, bindingContext);
}
return model;
}
#endregion
private void addRequestValues(JsonDictionary model, NameValueCollection nameValueCollection, ControllerContext controllerContext, ModelBindingContext bindingContext)
{
foreach (string key in nameValueCollection.Keys)
{
if (bindingContext.PropertyFilter(key))
{
var jsonText = nameValueCollection[key];
var newModel = deserializeJson(jsonText);
// Add the new JSON key/value pairs to the Model
model.Add(newModel);
}
}
}
private JsonDictionary deserializeJson(string json)
{
// Must Reference "System.Web.Extensions" in order to use the JavaScriptSerializer
var serializer = new System.Web.Script.Serialization.JavaScriptSerializer();
return serializer.Deserialize<JsonDictionary>(json);
}
}
This is what I tried. Saves a lot of work. Javascript:
var dict = {};
dict["id"] = "200";
dict["FirstName"] = "Chris";
dict["DynamicItem1"] = "Some Value";
dict["DynamicItem2"] = "Some Other Value";
var theObject = {};
theObject.dict = dict;
$.post(URL, theObject, function (data, textStatus, XMLHttpRequest) {
console.log("success");
}, "json");
Action 1 Method:
public ActionResult MethodName(DictionaryModel obj)
{
//Action method logic
}
public class DictionaryModel
{
public Dictionary<string, string> dict { get; set; }
}
It's possible with custom model binders 5 or filters. Behind the scenes - you will 4 have to do it manually anyway (Request.Form, parse 3 strings, create dictionary tralala), but 2 at least - your controller will be clean 1 and code will be reusable for another actions.
I don't think it's possible to pass in a 19 Dictionary from jQuery/Ajax to an ActionResult 18 method via an Http Post. One thing I figured 17 out that seems to be the easiest to work 16 with is to pass in a JSON object and then 15 parse that out into a Dictionary.
Here's 14 the modified version of of the above calling 13 "$.post" from jQuery that sends JSON as 12 a pseudo-Dictionary:
$.post("/Controller/AddItems",
{
values: Sys.Serialization.JavaScriptSerializer.serialize(
{
id: 200,
"name": "Chris"
}
)
},
function(data) { },
"json");
The "Sys.Serialization.JavaScriptSerializer.serialize" function 11 is a method of the ASP.NET AJAX JavaScript 10 library.
Here's the modified version of the 9 above ActionResult method:
public ActionResult AddItems(Dictionary<string, object> values)
{
// Must Reference "System.Web.Extensions" in order to use the JavaScriptSerializer
var json = new System.Web.Script.Serialization.JavaScriptSerializer();
var data = json.Deserialize<Dictionary<string, string>>(routeValues);
// do something
}
I think this makes 8 it much easier to Unit Test by passing JSON, instead 7 of using the Form Collection to send/retrieve 6 the collection of key/value pairs. Also, it's 5 easier to get working than figuring out 4 how to build a custom IModelBinder, and 3 a custom IModelBinder might cause issues 2 with other ActionResult methods when this 1 is the only one I need to do this.
DefaultModelBinder is able to bind your 4 POST to array or dictionary. For example:
for 3 arrays:
public ActionResult AddItems(string[] values)
$.post("/Controller/AddItems", { values: "values[0]=200&values[1]=300" },
function(data) { }, "json");
or:
$.post("/Controller/AddItems", { values: "values=200&values=300" },
function(data) { }, "json");
for dictionaries:
public ActionResult AddItems(Dictionary<string, object> values)
$.post("/Controller/AddItems", {
values: "values[0].Key=value0&values[0].Value=200&values[1].Key=value1&values[1].Value=300" }, function(data) { }, "json");
UPDATED:
If your values 2 are in HTML inputs then in jQuery you can 1 do something like this:
var postData = $('input#id1, input#id2, ..., input#idN").serialize();
// or
var postData = $('input.classOfYourInputs").serialize();
$.post("/Controller/AddItems", { values: postData }, function(data) { }, "json");
UPDATED:
Also check this: Scott Hanselman's ComputerZen.com - ASP.NET Wire Format for Model Binding to Arrays, Lists, Collections, Dictionaries
This is an old post but I can't help having 15 a few remarks anyway.
@eu-ge-ne: "DefaultModelBinder 14 is able to bind your POST to array or dictionary." True 13 but at least for dictionaries I find the 12 required form notation rather counterintuitive.
@Chris: Yesterday 11 I had exactly the same problem while trying 10 to post a JavaScript (JSON) dictionary to 9 a controller action method. I worked out 8 a totally different custom model binder 7 that processes generic dictionaries with 6 different type arguments. I have only tested 5 it in MVC 3 and probably had the advantage 4 of an improved framework.
For the details 3 of my experiences and the source code of 2 the custom model binder, please see my blog 1 post at http://buildingwebapps.blogspot.com/2012/01/passing-javascript-json-dictionary-to.html
More Related questions
We use cookies to improve the performance of the site. By staying on our site, you agree to the terms of use of cookies.