[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public void Auth(string username)
{
    string password = "";
    using (SqlConnection con = new SqlConnection(GetConnectionString()))
    {
        SqlCommand cmd = new SqlCommand("Select PASSWORD from users where USERNAME = '" + username + "'", con);

        //Open Connection
        con.Open();

        //To Read From SQL Server
        SqlDataReader dr = cmd.ExecuteReader();

        while (dr.Read())
        {
            password = dr["PASSWORD"].ToString();
        }

        //Close Connection
        dr.Close();
        con.Close();
        this.Context.Response.ContentType = "application/json; charset=utf-8";
        this.Context.Response.Write(password);

    }
}

service.Login = function (username, password, callback) {
        var q = $q.defer;
        $http({
            url: 'services/ShiftLogService.asmx/Auth',
            dataType: "json",
            method: "POST",
            data: { username: username }
        }).success(function (data) {
            console.log(data);
        }).error(function (data) {
           // q.reject();
        });
        return q.promise;

    };

SyntaxError: Unexpected token l
at Object.parse (native)
at uc (http://localhost:15380/bower_components/angular/angular.min.js:17:6)
at ac (http://localhost:15380/bower_components/angular/angular.min.js:90:253)
at http://localhost:15380/bower_components/angular/angular.min.js:91:164
at q (http://localhost:15380/bower_components/angular/angular.min.js:7:355)
at ed (http://localhost:15380/bower_components/angular/angular.min.js:91:146)
at c (http://localhost:15380/bower_components/angular/angular.min.js:92:403)
at http://localhost:15380/bower_components/angular/angular.min.js:128:305
at m.$eval (http://localhost:15380/bower_components/angular/angular.min.js:142:467)
at m.$digest (http://localhost:15380/bower_components/angular/angular.min.js:140:47)(anonymous function) @ angular.js:13363(anonymous function) @ angular.js:10162(anonymous function) @ angular.js:15621m.$eval @ angular.js:17059m.$digest @ angular.js:16771m.$apply @ angular.js:17121g @ angular.js:11298x @ angular.js:11561v.onload @ angular.js:11624