Call web service from js file(angularjs)

i am creating a web app in MVC5 in which i need to call a web service from my javascript file,

in asp.net i used to call like

$http.get('/welcome.asmx/welcomegrid', {
        params: {
        }
    })

but in MVC5 it is showing me error

Request format is unrecognized for URL unexpectedly ending in '/welcomegrid'

i tried this also

$http.get("http://localhost:50353/Models/welcome.asmx/welcomegrid", {
        params:
        {

        }
    })

but i am facing the same error