Given that in .NET the System.String class is sealed, how do you create a simple domain-specific string class so you can use type checking to ensure that the correct sort of string is used? Do you have a favourite implementation of such a class?
鉴于在.NET中System.String类是密封的，如何创建一个简单的特定于域的字符串类，以便您可以使用类型检查来确保使用正确的字符串类型？你有这样一个班级最喜欢的实现吗？
You might, for example, want to create a class to represent an email address to ensure that email is not accidentally sent to someone's postal address. Although that's not a great example I'm thinking about the cases where all you need is the type safety but no additional logic or validation.
例如，您可能希望创建一个表示电子邮件地址的类，以确保不会意外地将电子邮件发送到某人的邮政地址。虽然这不是一个很好的例子，但我正在考虑的情况是，你需要的只是类型安全，但没有额外的逻辑或验证。
2 个解决方案
#1
5
You can wrap the string class in one of your own and add all the type checking you want.
您可以将字符串类包装在自己的类中，并添加所需的所有类型检查。
Think composition, instead of inheritance.
想想组合，而不是继承。
#2
0
You might be interested in http://msdn.microsoft.com/en-us/library/system.net.mail.mailaddress.aspx in terms of your e-mail address example.
根据您的电子邮件地址示例，您可能对http://msdn.microsoft.com/en-us/library/system.net.mail.mailaddress.aspx感兴趣。
#1
5
You can wrap the string class in one of your own and add all the type checking you want.
您可以将字符串类包装在自己的类中，并添加所需的所有类型检查。
Think composition, instead of inheritance.
想想组合，而不是继承。
#2
0
You might be interested in http://msdn.microsoft.com/en-us/library/system.net.mail.mailaddress.aspx in terms of your e-mail address example.
根据您的电子邮件地址示例，您可能对http://msdn.microsoft.com/en-us/library/system.net.mail.mailaddress.aspx感兴趣。