zoukankan html css js c++ java

改变this 指向的3种方法

1.在函数内部声明一个that，然后将this赋值给that,

var that=this;

最后用that 代替this使用

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    
</body>
<script>
    const team={
        members:["Herry","hrll"],
        teamName:"Es6",
        teamSummary:function() {
            var that=this;
            return this.members.map(function(member) {
                return `${member}隶属于${that.teamName}`
            })
        }
    }
    console.log(team.teamSummary())
</script>
</html>

2.用bind方法，绑定外部的this

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    
</body>
<script>
    const team={
        members:["Herry","hrll"],
        teamName:"Es6",
        teamSummary:function() {
            
            return this.members.map(function(member) {
                return `${member}隶属于${this.teamName}`
            }.bind(this))
        }
    }
    console.log(team.teamSummary())
</script>
</html>

3.直接使用箭头函数

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
    
</body>
<script>
    const team={
        members:["Herry","hrll"],
        teamName:"Es6",
        teamSummary:function() {
            
            return this.members.map((member)=> {
                return `${member}隶属于${this.teamName}`
            })
        }
    }
    console.log(team.teamSummary())
</script>
</html>

3个显示效果：

查看全文

相关阅读:
光盘和U盘
 解决时间同步
 僵尸进程和孤儿进程
 Centos虚拟机设置网络模式
 常用CDN 和后台管理模板
 微信小程序wxs如何使用
 kubernetes/client-go--使用 Clientset 获取 Kubernetes 资源对象
 samplecontroller
volcano
DNS欺骗

原文地址：https://www.cnblogs.com/guangzhou11/p/9638639.html