foods
对象示例。如果我们想删除apples
键,我们可以使用delete
关键字删除它,如下所示: 删除foods.apples;
foods
对象中删除oranges
, plums
和strawberries
键。 foods
对象只有三个键: apples
, grapes
和bananas
testString: 'assert(!foods.hasOwnProperty("oranges") && !foods.hasOwnProperty("plums") && !foods.hasOwnProperty("strawberries") && Object.keys(foods).length === 3, "The foods
object only has three keys: apples
, grapes
, and bananas
");'
- text: 使用delete
oranges
, plums
和strawberries
键
testString: 'assert(code.search(/oranges:/) !== -1 && code.search(/plums:/) !== -1 && code.search(/strawberries:/) !== -1, "The oranges
, plums
, and strawberries
keys are removed using delete
");'
```