http patch to only update certain fields

Can i use http patch with the web api to update only certain fields from my entity model ?
Can someone possibly provide some pseudo code or maybe a working example ?

If i can't use patch what is the common alternative aproach to update only certain fields with the web api ?

Re: http patch to only update certain fields

According to this http://aspnetwebstack.codeplex.com/workitem/3 , Web API already supports PATCH verb.

According to http://aspnetwebstack.codeplex.com/discussions/350398 , Web API supports AcceptVerbsAttribute so you can define PATCH using the attribute.

This works (although actually does not what PATCH is suppose to do but my point is PATCH verb already supported):

[AcceptVerbs("PATCH")]
public string Patch()
{
return "Patch!";
}

In terms of functionality, you need to:

Define method so that it accepts PATCH
Define parameter representing your model and id of the parent
using id of the parent get the parent model
update the parent model using the model passed in
Save back to database

Re: http patch to only update certain fields

Thank you aliostad, i took a look at those documents, i'm not sure however how to exactly implement that.
Could you provide some very simple pseude code , i am not sure what the api controller method should look like.

Re: http patch to only update certain fields

Please see my updates.

Re: http patch to only update certain fields

Thank you for your exmple, i'm still not completly clear on how to use this. Allow me to demonstrate.

Assume i have this model

public partial class Todo
{
    public int id { get; set; }
    public string content { get; set; }
    public bool done { get; set; }
}

And i send this as json data to my controller as a patch request.
This is mearly the action of toggeling a checkbox.
I think it makes sence that i only want to sent that to my server, and not the entire model.

{ "id":1, "done" : true }

This is my controller

[AcceptVerbs("PATCH")]
public string Patch( Todo todo )
{
/*

How do i determine wich JSON values where submitted ?
How do i send only the submitted JSON values to the database ?

*/
}

It seems like a very basic thing to do, but i can't seem to get it right !
Thank you for your time.

Re: http patch to only update certain fields

ASP.NET Web API seems to be missing `UpdateModel`, `TryUpdateModel`, etc.

In ASP.NET MVC, you could use them to achieve the desired effect. I have created a work item in ASP.NET Web Stack which you can vote for.

Work item: http://aspnetwebstack.codeplex.com/workitem/102