js无法直接比较一个对象是否为空( obj === {} 永远为 false )，原因是js在对比两者时是比对的两者的内存地址，而 {} 放在js引擎新分配的内存地址中，故而两者永远不相等。
Object.getOwnPropertyNames()
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| let isEmpty = (Object.getOwnPropertyNames(obj).length === 0);
|
Object.keys()
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| let isEmpty = (Object.keys(obj).length === 0);
|
JSON.stringify()
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| const isEmpty = obj => JSON.stringify(obj) === "{}"
|
for…in
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| const isEmpty = obj => {
for (var key in obj) {
return false;
}
return true;
}
|
Reflect.ownKeys()
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| const isEmpty = obj => Reflect.ownKeys(obj).length === 0 && obj.constructor === Object
|
jQuery中的isEmptyObject()
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| let isEmpty = $.isEmptyObject(obj);
|
updated on: 2021-12-06
