问题描述
我是 C# 新手；请告诉我什么是坏的；
I'am new in C#;Please tell me what is bad;
我对这条消息有一个错误:
I have an error with this MESSAGE:
无法将类型Factory.ContactSite"隐式转换为Factory.Site""
我的代码:
class SiteFactory {
public enum SiteType {
Contact, Gallery, Info, News
}
public static Site makeSite(SiteType type) {
switch (type) {
case SiteType.Contact:
{
return new ContactSite(); //create new object
}
case SiteType.Info:
{
return new InfoSite(); //create new object
}
default:
return null;
}
}
}
//-------------------------------------------------------------
//-----------------------------------------------------------------
class Site {
public bool generate(String patch) {
System.IO.FileStream f = new FileStream(patch, FileMode.Create);
return true;
}
}
//--------------------------------------------------------主要:
//------------------------------------------------------------main:
SiteFactory.makeSite(SiteFactory.SiteType.Contact).generate("file.txt");
class ContactSite 当前为空
class ContactSite is currently empty
推荐答案
我猜你需要做的是从 Site 派生类 InfoSite 和 ContactSite 像这样:
I guess what you need to do is derive the classes InfoSite and ContactSite from Site like this:
public class ContactSite : Site
{
}
public class InfoSite : Site
{
}
当您调用 makeSite 以获取实例时，您必须将其转换为正确的 type，如下所示:
when you call makeSite to get an Instance you would have to cast it into the right type like this:
InfoSite infSite = SiteFactory.makeSite(SiteFactory.SiteType.Contact) as InfoSite;
这篇关于c# 不能将类型 '' 隐式转换为 ''的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！