如何写一个解释一个getter和setter？ [英] How to write a getter and setter for a Dictionary?

问题描述

你是如何定义的复杂数据类型的一个getter和setter如字典

How do you define a getter and setter for complex data types such as a dictionary?

public Dictionary<string, string> Users
{
    get
    {
        return m_Users;
    }

    set
    {
        m_Users = value;
    }
}

这返回整个字典？你可以写二传手来看看，看看，如果一个特定的键值对存在，然后如果它没有，添加它。否则更新当前的键值对？对于GET，可以返回一个特定的键值对，而不是整个字典的？

This returns the entire dictionary? Can you write the setter to look and see if a specific key-value pair exists and then if it doesn't, add it. Else update the current key value pair? For the get, can you return a specific key-value pair instead of the whole dictionary?

推荐答案

这是不可能做到它在将仅涉及属性的方法。您的理论上的可以写一个二传手，但对于一个getter，你就需要指定要检索的关键。既然属性不接受参数是不可能的。自然的方式来完成你想要的是使用方法：

It is not possible to do it in a way that would involve only properties. You theoretically could write a setter, but for a getter, you would need to specify a key that you want to retrieve. That is impossible since properties do not accept parameters. Natural way to accomplish what you want would be to use methods:

private Dictionary<string, string> users = new Dictionary<string, string>();

public void Set(string key, string value)
{
    if (users.ContainsKey(key))
    {
        users[key] = value;
    }
    else
    {
        users.Add(key, value);
    }
}

public string Get(string key)
{
    string result = null;

    if (users.ContainsKey(key))
    {
        result = users[key];
    }

    return result;
}

另外，正如其他人已经说过，你可以使用索引，但我已经总是发现他们有点麻烦。但我想这只是个人喜好的问题。

Alternatively, as others have already said, you could use indexers, but I've always found them a little cumbersome. But I guess it's just a matter of personal preference.

和只是为了完整起见，这是一个二传手如何模样，虽然这是极不寻常，反直观地有这样的属性：

And just for the sake of completeness, this is how a setter could look like, although it's highly unusual and counter-intuitive to have such a property:

public KeyValuePair<string, string> Users
{
    set
    {
        Set(value.Key, value.Value);
    }
}

在内部，它使用了我以前的片段设置方法。

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