开关盒故障 [英] switch case failure

问题描述

以下是我的程序的摘录，我将其分离出来并将

编译为自己的程序。


问题在于一个案例测试为真，所有案例都在下面

它也会执行。因此，如果用户输入4，将执行来自

情况4-9的语句。


（我用cout替换函数调用进行测试。）


我正在使用Win2k，Open Watcom IDE v 1.3。


这已经在程序的几个地方进行了测试。


（ps - 它按原样编译，它也可以与所有

注释掉的库完好无损 - 无论哪种方式都出现相同的错误）



// #include< stdio.h>

#include< stdlib.h>

#include< iostream.h> //而不是使用命名空间std

// #include< string.hpp>

// #include< fstream.h>

// #include< istream>

// #include" Fcopy.h"

// #include< ctime>

// #include< math.h>

int main（）

{

int menu_select_int = -1;


do

{

system（" CLS"）;

cout<<" * ********************* MENU ********************* ** \ n" ;;

cout<< "创建或编辑输入文件.......... 1 \ n" ;;

cout<< "计算器。没有。阶段................ 2 \ n" ;;

cout<< "数据图.......................... 3 \ n" ;;

cout<< " RR与阶段的数量............... 4 \ n" ;;

cout<< " McCabe Thiele情节................. 5 \ n" ;;

cout<< "打印输入文件............ 6 \ n" ;;

cout<< "托盘组合物的打印输出.7 \ n" ;;

cout<< " vle数据的打印输出........... 8 \ n" ;;

cout<< "退出............................... 9 \ n" ;;

cout<< ; " ********** * \ n \ n" ;;

cout<< MENU：" ;;

cin>> menu_select_int;


开关（menu_select_int）

{


案例1：

cout<< \\\
going to input data function \\\
;

cout<< 案例1;

cin.ignore（）;


案例2：

cout<< \ ingo to CNOS function\\\
;

cout<< 案例2;

cin.ignore（）;


案例3：

cout<< \ ingo to DP function\\\
;

cout<< 案例3;

cin.ignore（）;


案例4：

cout<< \\ tonging to RR vs function\\\
;

cout<< 案例4;

cin.ignore（）;


案例5：

cout<< \\\
going to McTh function\\\
;

cout<< 案例5;

cin.ignore（）;


案例6：

cout<< \ ninging to PIF function\\\
;

cout<< 案例6;

cin.ignore（）;


案例7：

cout<< \\\
going to printout function\\\
;

cout<< 案例7;

cin.ignore（）;


案例8：

cout<< \ ingo to PO VLE function\\\
;

cout<< 案例8;

cin.ignore（）;


案例9：

cout<< \\\
going to AYS - end function\\\
;

cout<< case 9;

cin.ignore（）;

} //结束开关盒

} while（menu_select_int！= 9） ;


cin.ignore（）;

返回（0）;


}

解决方案

YitzHandel写道：

以下是我程序的摘录，我是分离出来并编译为自己的程序。

问题是，只要案例测试成立，下面的所有案例都会执行。因此，如果用户输入4，将执行来自案例4-9的语句。

（我用cout替换函数调用进行测试。）

我我正在使用Win2k，Open Watcom IDE v 1.3。

这已经在程序的几个地方进行了测试。

（ps - 它按原样编译，它也很好地编译所有
注释掉的库 - 无论哪种方式都出现错误）

//＃include< stdio.h>
#include< stdlib.h>
#include< iostream.h> //而不是使用命名空间std
// #include< string.hpp>
// #include< fstream.h>
// #include< istream>
// #include" Fcopy.h"
// #include< ctime>
// #include< math.h>

int main（）
{menu_select_int = -1;

做
{
系统（CLS）;
cout<<" ; ********************** MENU ********************* ** \ n ;;
cout<< "创建或编辑输入文件.......... 1 \ n" ;;
cout<< "计算器。没有。阶段................ 2 \ n" ;;
cout<< "数据图.......................... 3 \ n" ;;
cout<< " RR与阶段数相对............... 4 \ n" ;;
cout<< " McCabe Thiele情节................. 5 \ n" ;;
cout<< "打印输入文件............ 6 \ n" ;;
cout<< "托盘组合物的打印输出.7 \ n" ;;
cout<< " vle数据的打印输出........... 8 \ n" ;;
cout<< "退出............................... 9 \ n" ;;
cout<< " ********** * \ n \ n" ;;
cout<< MENU：" ;;
cin>> menu_select_int;

开关（menu_select_int）
{/>
案例1：
cout<< 输入数据函数\ n;&＃;> cout<< case 1;
cin.ignore（）;

添加break在每个案例之后你都不想要

来说明下一个案例...


-David

优异。有效。谢谢。

YitzHandel写道：

以下是我程序的摘录，我把它分开并编译成自己的程序。

问题是，一旦案例测试成立，下面的所有案例都会执行。因此，如果用户输入4，将执行来自案例4-9的陈述。

[snip]


你需要在每个案例body之后插入break语句。默认情况下

（不幸的是），switch语句会失效。这是一个例子：


开关（some_int）

{

案例1：

cout<< 案例1 <<结束;

休息;

案例2：

cout<< 案例2 <<结束;

休息;

默认值：

cout<< 默认情况 <<结束;

}


干杯！ --M

The following is an extract from my program, which I seperated out and
compiled as its own program.

The problem is that as soon as a case tests true, all the cases below
it execute as well. So if the user inputs, 4, the statements from
cases 4-9 will execute.

(I replaced function calls with cout for testing.)

I am using Win2k, Open Watcom IDE v 1.3.

This has tested as happening in several places in the program.

(p.s. - it compiles as is, it also compliles fine with all the
commented out libraries - same error either way)


//#include <stdio.h>
#include <stdlib.h>
#include <iostream.h> // instead of using namespace std
//#include <string.hpp>
//#include <fstream.h>
//#include <istream>
//#include "Fcopy.h"
//#include <ctime>
//#include <math.h>
int main ()
{
int menu_select_int =-1;

do
{
system("CLS");
cout <<"**********************MENU********************* **\n";
cout << " Create Or Edit Input File..........1\n";
cout << " Calc. no. of stages................2\n";
cout << " Data plot..........................3\n";
cout << " RR vs. No. Of stages...............4\n";
cout << " McCabe Thiele plot.................5\n";
cout << " Printout the input file............6\n";
cout << " Printout of the tray compositions..7\n";
cout << " Printout of the vle data...........8\n";
cout << " Quit...............................9\n";
cout << "************************************************* \n\n";
cout << "MENU: ";
cin >> menu_select_int;

switch (menu_select_int)
{

case 1:
cout << "\ngoing to input data function\n";
cout << "case 1";
cin.ignore();

case 2:
cout << "\ngoing to CNOS function\n";
cout << "case 2";
cin.ignore();

case 3:
cout << "\ngoing to DP function\n";
cout << "case 3";
cin.ignore();

case 4:
cout << "\ngoing to RR vs function\n";
cout << "case 4";
cin.ignore();

case 5:
cout << "\ngoing to McTh function\n";
cout << "case 5";
cin.ignore();

case 6:
cout << "\ngoing to PIF function\n";
cout << "case 6";
cin.ignore();

case 7:
cout << "\ngoing to printout function\n";
cout << "case 7";
cin.ignore();

case 8:
cout << "\ngoing to PO VLE function\n";
cout << "case 8";
cin.ignore();

case 9:
cout << "\ngoing to AYS - end function\n";
cout << "case 9";
cin.ignore();
} //end switch case
} while (menu_select_int != 9);

cin.ignore();
return(0);

}

解决方案

YitzHandel wrote:

The following is an extract from my program, which I seperated out and
compiled as its own program.

The problem is that as soon as a case tests true, all the cases below
it execute as well. So if the user inputs, 4, the statements from
cases 4-9 will execute.

(I replaced function calls with cout for testing.)

I am using Win2k, Open Watcom IDE v 1.3.

This has tested as happening in several places in the program.

(p.s. - it compiles as is, it also compliles fine with all the
commented out libraries - same error either way)


//#include <stdio.h>
#include <stdlib.h>
#include <iostream.h> // instead of using namespace std
//#include <string.hpp>
//#include <fstream.h>
//#include <istream>
//#include "Fcopy.h"
//#include <ctime>
//#include <math.h>
int main ()
{
int menu_select_int =-1;

do
{
system("CLS");
cout <<"**********************MENU********************* **\n";
cout << " Create Or Edit Input File..........1\n";
cout << " Calc. no. of stages................2\n";
cout << " Data plot..........................3\n";
cout << " RR vs. No. Of stages...............4\n";
cout << " McCabe Thiele plot.................5\n";
cout << " Printout the input file............6\n";
cout << " Printout of the tray compositions..7\n";
cout << " Printout of the vle data...........8\n";
cout << " Quit...............................9\n";
cout << "************************************************* \n\n";
cout << "MENU: ";
cin >> menu_select_int;

switch (menu_select_int)
{

case 1:
cout << "\ngoing to input data function\n";
cout << "case 1";
cin.ignore();

Add a "break" statement after every case you don''t want
to fall through to the next case...

-David

excellent. that worked. thanks.

YitzHandel wrote:

The following is an extract from my program, which I seperated out and
compiled as its own program.

The problem is that as soon as a case tests true, all the cases below
it execute as well. So if the user inputs, 4, the statements from
cases 4-9 will execute.

[snip]

You need to insert break statements after each case "body". By default
(unfortunately), switch statements fall through. Here''s an example:

switch( some_int )
{
case 1:
cout << "Case 1" << endl;
break;
case 2:
cout << "Case 2" << endl;
break;
default:
cout << "Default case" << endl;
}

Cheers! --M

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