“Vue Object.defineProperty”的版本间的差异
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Jihongchang（讨论 | 贡献） |
Jihongchang（讨论 | 贡献） |
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| 第97行： | 第97行： | ||
Object.defineProperty(person, 'age', { | Object.defineProperty(person, 'age', { | ||
value:18, | value:18, | ||
| − | enumerable:true | + | enumerable:true //控制属性是否可以枚举，默认值是 false |
}) | }) | ||
//console.log(Object.keys(person)); | //console.log(Object.keys(person)); | ||
2024年7月28日 (日) 10:02的版本
https://www.bilibili.com/video/BV1Zy4y1K7SH?p=11
ES6 往对象上添加属性
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>回顾Object.defineProperty方法</title>
</head>
<body>
<script type="text/javascript">
let person = {
name:'张三',
sex:'男'
}
Object.defineProperty(person, 'age', {
value:18
})
console.log(person);
</script>
</body>
</html>
通过 Object.defineProperty 添加的属性遍历不到
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>回顾Object.defineProperty方法</title>
</head>
<body>
<script type="text/javascript">
let person = {
name:'张三',
sex:'男',
// age:18
}
Object.defineProperty(person, 'age', {
value:18
})
console.log(Object.keys(person));
console.log(person);
</script>
</body>
</html>
证明通过 Object.defineProperty 添加的属性不可枚举
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>回顾Object.defineProperty方法</title>
</head>
<body>
<script type="text/javascript">
let person = {
name:'张三',
sex:'男',
// age:18
}
Object.defineProperty(person, 'age', {
value:18
})
//console.log(Object.keys(person));
for (let key in person) {
console.log('@', person[key]);
}
console.log(person);
</script>
</body>
</html>
通过 enumerable:true 让 Object.defineProperty 添加的属性可枚举
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>回顾Object.defineProperty方法</title>
</head>
<body>
<script type="text/javascript">
let person = {
name:'张三',
sex:'男',
// age:18
}
Object.defineProperty(person, 'age', {
value:18,
enumerable:true //控制属性是否可以枚举，默认值是 false
})
//console.log(Object.keys(person));
for (let key in person) {
console.log('@', person[key]);
}
console.log(person);
</script>
</body>
</html>