如果我不知道变量的类型，如何从变量中清除以前的数据（可能是数组，对象或基元）

Question

Hi i am new in angular js or javascript.i don 't know how to clear previous data of variable,if i dont know type of variable ?

Comment.get()
    .success(function(data) {
        //here i have to clear previous data of $scope.data, but i dont know type of $scope.data
        $scope.data = data;
        $scope.loading = false;
    }); 

could you please suggest me how to clear previous data from variable $scope.data ?

Answer 1

In JavaScript there are no declaration of types of variable. So whatever the type of data that a variable contains it can be overwritten by any other types of data.

And by your function, its good as it is.

Answer 2

Depends on what you mean by "clear", but the typical way to clear a variable is like this:

delete $scope.data;

Then if you need to check that the variable is empty/exists you can do:

if ($scope.data !== undefined)

...or whatever. You don't need to assign the variable as an array or string when "clearing" it. JavaScript is not strongly typed.

However, as someone already pointed out in the comments you probably don't need to clear the variable at all because it is overwritten every time.