Javascript innerWidth 而不是 window.innerWidth

Question

有什么理由我应该使用window.innerWidth而不是innerWidth吗？

Answer 1

window.innerWidth is always a property of the window object, so you're safe as long as a window exists (in other js environments like Node.js it doesn't), while innerWidth refers to the global object only if there isn't already a variable with the same name in the current scope.

For example

// This logs the actual window.innerWidth
console.log(innerWidth);

function something() {
  const innerWidth = 4;

  // This innerWidth will not refer to the global object..
  console.log(innerWidth);
}

// ..so this logs 4
something();

So either you remember all of the window properties so you don't incur in conflicting variable names (not very handy and hard to debug) or you just access the window object explicitly, making the code a little more verbose but also clearer and less error-prone.