4.修改this指向.html 821 B

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <meta charset="UTF-8">
  5. <meta name="viewport" content="width=device-width, initial-scale=1.0">
  6. <title>Document</title>
  7. </head>
  8. <body>
  9. <script>
  10. let obj = {
  11. name: '图图'
  12. }
  13. function fn1(x,y) {
  14. const sum = x + y;
  15. console.log(sum,'sum')
  16. console.log(this,'this');
  17. console.log(this.name,'name')
  18. }
  19. // fn1.call(obj,2,3);
  20. // fn1.apply(obj,[2,3]);
  21. fn1.bind(obj,2,3)();
  22. /**
  23. * call bind apply
  24. * 1.call和apply可以直接调用,bind无法直接调用
  25. * 2.call和bind第二项开始 参数逐个传入
  26. * 3.apply第二项开始 参数需要放到数组中逐个传入
  27. */
  28. </script>
  29. </body>
  30. </html>