C#からParse.comのCloudFunctionを呼び出して結果を受け取る ref: http://qiita.com/tyfkda/items/be2858031203921bb505

main.js

  Parse.Cloud.define('getFoobars', function(request, response) {
    var query = new Parse.Query('Foobars');
    query.containedIn('foobarId', request.params.foobarIds);
    query.find({
      success: function(results) {
        response.success(results);
      },
      error: function() {
        response.error('find failed');
      }
    });
  });

RequestParseCloudFunction.cs

using Parse;

...

  public void RequestFoobars(List<string> foobarIds) {
    Dictionary<string, object> data = new Dictionary<string, object>();
    data.Add("foobarIds", foobarIds);
    ParseCloud.CallFunctionAsync<List<object>>("getFoobars", data).ContinueWith(t => {
        if (t.IsFaulted || t.IsCanceled || !t.IsCompleted || t.Result == null) {
          Debug.Log(t.Exception.GetBaseException().Message);
          return;
        }

        foreach (object obj in t.Result) {
          if (obj is ParseObject) {
            ParseObject pobj = obj as ParseObject;
            string foobarId = pobj.Get<string>("foobarId");
            DateTime? updatedAt = pobj.UpdatedAt;
            ...
          }
        }
      });
  }