As others have mentioned, there are two main differences:
- Method 1 will create a new function for every instance of User
- Method 1 will be able to access local variables in the constructor's scope
Here's an example to demonstrate these:
function User() {
var name = "my name";
this.foo = function() {
// one function per User instance
// can access 'name' variable
};
}
User.prototype.bar = function() {
// one function shared by all User instances
// cannot access 'name' variable
};
var a = new User();
var b = new User();
console.log(a.foo === b.foo); // false; each instance has its own foo()
console.log(a.bar === b.bar); // true; both instances use the same bar()
