英文:
TypeScript: How do you determine the type of an attribute whose name is set dynamically?
问题
我在看 TypeScript 并有一个问题。我正在初始化一个对象，稍后将填充动态键值对。该对象的类型应为 Clients。键（字符串）值（数字）是通过 forEach() 创建的。因此，当对象被创建后，它将如下所示：
type Clients = {}; // 这一行是我的问题！
const clients: Clients = {};
const htmlElementCollection: HTMLElement = document.querySelectorAll('.clients');
htmlElementCollection.forEach(c => {
clients[c.getAttribute('data-client-name')] = clients[c.getAttribute('data-client-value')];
});
// 结果：
clients = {
"A": 10.00,
"B": 20.00,
}
// 但也可能是：
clients = {
"D": 10.00,
"B": 20.00,
"E": 30.00
}
问题： 是否可以为动态键分配类型？
英文:
I am looking at typescript and have a question. I am initializing an object which I will later fill with dynamic key value pairs. The object should be of type Clients. The Key(String) Values(number) are created via a forEach(). Thus, when the object has been created, it would look like this:
type Clients = {}; // This line is my question!
const clients: Clients = {};
const htmlElementCollection: HTMLElement = document.querySelectorAll('.clients');
htmlElementCollection.forEach( c => {
clients[c.getAttribute('data-client-name')] = clients[c.getAttribute('data-client-value')];
});
// Result:
clients = {
"A": 10.00,
"B": 20.00,
}
// but also:
clients = {
"D": 10.00,
"B": 20.00,
"E": 30.00
}
Question: Is it possible to assign a type to dynamic keys?
答案1
得分: 1
你可以使用 Record 类型，将键分配为 string 类型，将值分配为数字类型。
因此，你可以如下所示设置 Clients 类型。
type Clients = Record<string, number>
你还可以为键设置类型，而不是将其分配为字符串类型。
查看 TypeScript 的官方文档中有关 Records 的信息此处。
英文:
You can use the Record type and have it assigning the keys to string and the value to number.
So you can set Clients type as follows.
type Clients = Record<string, number>
You can also set a type for the keys instead of assigning it to string.
Check the official docs of TypeScript for Records here
答案2
得分: 1
以下是您要的翻译：
"which translates to an object with keys of type string and values of type number"
翻译为：这意味着一个具有字符串类型键和数字类型值的对象。
英文:
The best you can do here is
type Clients = {
[k: string]: number,
};
which translates to an object with keys of type string and values of type number
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