$http.get("/merchantmall/merchant.json")
 .success(function(data, status, headers, config) {
  console.log(arguments);
 })
 .error(function(data, status, headers, config) {
  console.log(arguments);
 })

$http({url: "/merchantmall/merchant.json", })
 .success(function(data, status, headers, config) {
  console.log(arguments);
 })
 .error(function(data, status, headers, config) {
  console.log(arguments);
 })

var promise = $http({
 method: 'GET',
 url: '/api/users.json'
});
promise.then(function(resp) {
 // resp是一个响应对象
}, function(resp) {
 // 带有错误信息的resp
});

var promise = $http({
 method: 'GET',
 url: '/api/users.json'
});
promise.success(function(data, status, headers, config) {
 // 处理成功的响应
});
promise.error(function(data, status, headers, config) {
 // 处理非成功的响应
});