Then is not a function error in angularjs - angularjs

Question

I have simple function which returns employee data. But getting then is not a function error how to retrieve response from function
function getdata(criteria) {
return angularService.GetData(criteria, $scope.year, $scope.selectedYearType.name);
}
Which is called in below function
$scope.GetEmployeeData = function (criteria) {
$scope.searchMethod = getdata;
$scope.searchMethod().then(function (response) {----------> Error here
var totalEmployeeAmount = 0;
for (var i = 0; i < response.data.results.length; i++) {
var summaryData = response.data.results[i];
totalEmployeeAmount += (summaryData.totalEmployeeAmount);
}
return response
}, function (response) {
// This is to see if has any error
//console.log(response);
});
}
My angular service
function getData(criteria, year, yearType) {
var url = apiService.ApiUrl + "/Employees/EmployeeHistory/GetData/" + year + "/" + yearType;
return apiService.DeferredPost(url, criteria);}
Deferred Post Method
function deferredPost(url, params) {
var deferred = $q.defer();
$http.post(url, params)
.then(function (data) {
deferred.resolve(data);
}, function (resp) {
deferred.reject(resp);
}).catch(function (data) {
deferred.reject(data);
});
return deferred.promise;
}
API
var api = {
DeferredPost: deferredPost
};
return api;

Answer 1

Should be calling .then on searchMethod instead of searchMethod() - assuming getdata returns a promise as you can't call .then on a function that doesn't return a promise. Also I'm guessing you should be passing in the criteria as a parameter to getdata:
$scope.GetEmployeeData = function (criteria) {
$scope.searchMethod = getdata;
$scope.searchMethod.then(function (response) {
var totalEmployeeAmount = 0;
for (var i = 0; i < response.data.results.length; i++) {
var summaryData = response.data.results[i];
totalEmployeeAmount += (summaryData.totalEmployeeAmount);
}
return response
}, function (response) {
// This is to see if has any error
//console.log(response);
});
}

Answer 2

As #William Hampshire said, you should be using $scope.searchMethod.then(function ... ) instead of $scope.searchMethod().then(function ... )
$scope.GetEmployeeData = function (criteria) {
$scope.searchMethod = getdata(criteria);
$scope.searchMethod.then(function (response) {
var totalEmployeeAmount = 0;
for (var i = 0; i < response.data.results.length; i++) {
var summaryData = response.data.results[i];
totalEmployeeAmount += (summaryData.totalEmployeeAmount);
}
return response
}, function (response) {
// This is to see if has any error
//console.log(response);
});
}
The reason why your code is still failing is that you have a typo in your service name.
function getdata(criteria) {
return angularService.GetData(criteria, $scope.year, $scope.selectedYearType.name);
}
It should be GetData instead of getData.
function GetData(criteria, year, yearType) {
var url = apiService.ApiUrl + "/Employees/EmployeeHistory/GetData/" + year + "/" + yearType;
return apiService.DeferredPost(url, criteria);}