Passing and retrieving complex objects from Angularjs to Web Api - angularjs

Question

I have a form in angular where a user enters various criteria which I then want to pass to Web Api and get a result after queries are run. I originally thought of this as a "Get" but had trouble passing complex objects to the Web Api. With some advice, I then used a Post and was able to pass the criteria run the query in the Web Api but I had trouble getting the result back in Angular. The Web Api method is run and gets the results. But I don't see the results in the data service.
What is the best approach where the criteria for a query is multiple fields and some are lists? I haven't been able to find any good examples.
Here is the Web Api method:
[HttpPost]
public IEnumerable Post([FromBody] FrequentPawnerReportCriteria criteria)
{
var repo = new FrequentPawnerReport();
var result = repo.GetReport(criteria);
return result;
}`
Here is the dataservice:
function getFrequentPawner(criteria) {
return $http.post("/api/FrequentPawner/Post", criteria)
.then (getFrequentPawnerComplete)
.catch(getFrequentPawnerFailed);
function getFrequentPawnerComplete(response) {
var x = response
return response.data.results;
}
function getFrequentPawnerFailed(error) {
alert("XHR failed for frequent pawner report: " + error.responseText);
}
}
And here is the controller code:
function getTopPawnerResults(criteria) {
return DataContext.getFrequentPawner(criteria)
.then(
function (result) {
vm.frequentPawnerReport = result.data;
return vm.frequentPawnerReport;
});
}

Answer 1

Simply use JSON. Use JSON.stringify() to parse JSON object to string and POST it. Similarly, return JSON string from server, and assign it to variable in Angular. It will be automatically converted to JSON object.

Answer 2

I think when you make your post request, you need to have a callback function that would get invoked when your Web Api returns. Within that callback function you can update your $scope variables which will make your web ui show the response from the server. You can find an example of what I mean here: https://docs.angularjs.org/api/ng/service/$http
The gist of it:
$http({
method: 'POST',
url: '/path/to/your/web/api',
function(success) {
console.log('Successfully executed the api call');
$scope.response = response; // change this to match the data you are expecting from the server response
},
function(failure) {
console.error('There was an error');
$scope.failure = failure; // change this to match your failure response
}
);

Answer 3

Thanks for responding. The project is a mix of web forms and angularjs. I am migrating the app and didn't notice this form had a conflict which was causing a post back and making it look like the result was not being returned. I took the form into a separate project and was able to get the results I was going for.