切换命令有问题 [英] Problems with switch command
问题描述
我是一个csharp新手，我正在尝试通过一些代码并且已经得到了
我自己被困在一个循环中。任何帮助将不胜感激。
我有以下代码：
公共IDcCommand GetCommand（EnumProviders提供商）
{
开关（提供商）
{
案例EnumProviders.ODBC：
返回新的OdbcCommand（）;
case EnumProviders.SQLClient：
返回新的SqlCommand（）;
case EnumProviders.OLEDB（）：
返回new OleDbCommand（）;
}
}
如果我按原样保留代码，我会收到错误Control not not从
一个案例标签（''案例0：''）到另一个案件标签。如果我改变每个案例在返回行之后添加一个休息
，那么我得到一个无法访问的代码检测错误。怎么
我可以让这个代码工作吗？我认为回报应该是价值退出
。任何帮助都将非常感激。
谢谢，
Steve Bering
I am a csharp newbie and am trying to work through some code and have gotten
myself stuck in a loop. Any help would be appreciated.
I have the following code in place:
public IDcCommand GetCommand(EnumProviders provider)
{
switch( provider )
{
case EnumProviders.ODBC:
return new OdbcCommand();
case EnumProviders.SQLClient:
return new SqlCommand();
case EnumProviders.OLEDB():
return new OleDbCommand();
}
}
If I leave the code as is, I get the error "Control cannot fall through from
one case label (''case 0:'') to another". If I change each case to add a break
after the return line, then I get an unreachable code detected error. How
can I get this code to work? I thought a return was supposed to a value exit
from a fall through. Any help would be most appreciated.
Thanks,
Steve Bering
推荐答案
Steve，
Steve,
case EnumProviders.OLEDB（）：
case EnumProviders.OLEDB():
删除此行的括号。
Mattias
-
Mattias Sj？gren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/
请回复新闻组。
Remove the parentheses on this line.
Mattias
--
Mattias Sj?gren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/
Please reply only to the newsgroup.
是的，我犯了这个错误，但那只是在帖子中。
开关问题的任何想法？
谢谢，
Steve Bering
" Mattias Sj？gren" <毫安******************** @ mvps.org>在消息中写道
新闻：ey ************** @ TK2MSFTNGP11.phx.gbl ...
Yes, I made that mistake, but that was just in the post. Any ideas of the
switch issue?
Thanks,
Steve Bering
"Mattias Sj?gren" <ma********************@mvps.org> wrote in message
news:ey**************@TK2MSFTNGP11.phx.gbl...
Steve，
Steve,
case EnumProviders.OLEDB（）：
case EnumProviders.OLEDB():
删除此行上的括号。
Mattias
-
Mattias Sj？gren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/
请仅回复新闻组。
Remove the parentheses on this line.
Mattias
--
Mattias Sj?gren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/
Please reply only to the newsgroup.
添加在你的情况发生之后打破陈述并且你不会从一个到另一个掉落'
。
EX：
开关（条件）
{
case< test-condition>：
//做某事
休息; //这就是你所缺少的
case< test-condition>：
//这个东西
break;
}
" Steve Bering" < ST ********* @ hotmail.com>在留言中写道
新闻：我们************** @ TK2MSFTNGP12.phx.gbl ...
Add break statements after your case condition and you won''t ''fall thru''
from one to the other.
EX:
switch (condition)
{
case <test-condition>:
//do something
break; //this is what you are missing
case <test-condition>:
//something
break;
}
"Steve Bering" <st*********@hotmail.com> wrote in message
news:us**************@TK2MSFTNGP12.phx.gbl...
我是csharp新手并且我正在尝试通过一些代码并让
陷入循环中。任何帮助将不胜感激。
我有以下代码：
公共IDcCommand GetCommand（EnumProviders提供商）
{
开关（提供商）
{
案例EnumProviders.ODBC：
返回新的OdbcCommand（）;
案例EnumProviders.SQLClient：
返回新的SqlCommand（）;
案例EnumProviders.OLEDB（）：
返回新的OleDbCommand（）;
}
如果我按原样保留代码，我会收到错误控制不能通过
从一个案例标签（''案例0：''）到另一个案例标签。如果我更改每个案例以在返回行后添加
中断，那么我会收到无法访问的代码检测错误。如何才能让这段代码运行起来？我认为回报应该是价值
退出。任何帮助都将不胜感激。
谢谢，
Steve Bering
I am a csharp newbie and am trying to work through some code and have gotten myself stuck in a loop. Any help would be appreciated.
I have the following code in place:
public IDcCommand GetCommand(EnumProviders provider)
{
switch( provider )
{
case EnumProviders.ODBC:
return new OdbcCommand();
case EnumProviders.SQLClient:
return new SqlCommand();
case EnumProviders.OLEDB():
return new OleDbCommand();
}
}
If I leave the code as is, I get the error "Control cannot fall through from one case label (''case 0:'') to another". If I change each case to add a break after the return line, then I get an unreachable code detected error. How
can I get this code to work? I thought a return was supposed to a value exit from a fall through. Any help would be most appreciated.
Thanks,
Steve Bering
这篇关于切换命令有问题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IT屋！
