input.c

图书借阅管理程序v1.2

/****一些特殊的输入函数****/
#include<conio.h>
#include<stdio.h>
#include<string.h>
#include<stdlib.h>
#include<bios.h>



/****函数get_key(void)用于读取键盘按按钮****/
int get_key(void);
/**本函数专用于输入书号,返回所输入的号码**/
int InputBookNum();
/**本程序专用于输入书价,返回所输入的价格**/
float InputBookPrice();
/**input Yes or No,返回Y或者N**/
char *InputYesorNo();
/**本程序专门用于输入书名,返回书名字符串**/
char* InputBookName();

/*--------------注意:这些输入函数都支持ESC键,
当函数的返回类型为字符串时,按ESC返回NULL,
当函数的返回工为数字时,按ESC返回CANCEL (注:CANCEL宏定义为-1)
---------------*/

/****函数get_key(void)用于读取键盘按按钮(支持鼠标)****/
/*--------bioskey(0)的返回值为16位,如果低8位为非0,则是ASCII码,
如果低8 位为0,则高8位为扩充键盘码---------*/


/*------------------
int get_key(void)
{
  union keycode_type key;
  key.word=bioskey(0);
  return key.byte?key.byte:key.word;
 }
---------------------*/

int get_key(void)
{
 union keycode_type key;
 int button;
 /***如果既没有按鼠标也没有按键盘则一直循环**/
 do{
     /**--查看是否按下鼠标按钮,如果是,等待其释放--**/
     button=get_mouse_status(&mx,&my);
     if(button)
       while(get_mouse_status(&mx,&my));
     /**--查看键盘是否有键按下,如果是读其码--**/
     key.word=bioskey(1);
      if(key.word)
          key.word=bioskey(0);
     }while(button==0&&key.word==0);
  /**----返回鼠标按钮或者键盘码(ASCII码或扩展码)---**/
   if(button!=0)
     return button;
   else
     return key.byte?key.byte:key.word;
}


/*******************本函数专用于输入书号********************/
int InputBookNum()
{
 int key,count=0,num=0;
 char *string;
 string=(char*)malloc(7);
get: while((key=get_key())!=ENTER){
      switch(key){
      case'-':
             case '0':
             case '1':
             case '2':
             case '3':
             case '4':
             case '5':
             case '6':
             case '7':
             case '8':
             case '9':if(count>=6) continue;
                      putch(key);
                      string[count]=key;
                      count++;
                      break;

             case BACK:cprintf("\b");
                       putch('\0');
                       cprintf("\b");
                       count--;
                       if(count<=0) count=0;
                       break;
             case ESC: return(CANCEL);
             case '\0':
             case RIGHT:
             case LEFT:
             case DOWN:
             case PGUP:
             case PGDOWN:
             case HOME:
             case END:
             case UP:break;
             default:continue;
               }
         }
string[count]='\0';
if(string[0]=='\0') goto get;
sscanf(string,"%d",&num);
free(string);
return (num);
}



/*********************本程序专用于输入书价*************************/
float InputBookPrice()
{
 int key,count=0;
 float bookprice=0;
 
 char *bookpricestr;
 bookpricestr=(char*)malloc(6);
 gotoxy(3,7);
get: while((key=get_key())!=ENTER)
      {
        switch(key)
         {
             case '.':
             case '0':
             case '1':
             case '2':
             case '3':
             case '4':
             case '5':
             case '6':
             case '7':
             case '8':
             case '9':if(count>=5) break;
                      putch(key);
                      bookpricestr[count]=key;
                      count++;
                      break;

             case BACK:if(count==0) break;
                     cprintf("\b");
                     putch('\0');
                     cprintf("\b");
                     count--;
                     if(count<=0) count=0;
                     break;
            case ESC:return(CANCEL);
             case '\0':
             case RIGHT:
             case LEFT:
             case DOWN:
             case PGUP:
             case PGDOWN:
             case HOME:
             case END:
             case UP:break;
            default:break;
         }
      }
 bookpricestr[count]='\0';
 if(bookpricestr[0]=='\0') goto get;
 bookprice=atof(bookpricestr);
 free(bookpricestr);
return(bookprice);
}



/*******************input Yes or No******************/
char *InputYesorNo()
{
 char* yesorno;
 int key,count=0;
 yesorno=(char*)malloc(2);
get: while((key=get_key())!=ENTER)
      {
       if(key==SPACE) break;
         switch(key)
           {
            case'y':
            case'Y':if(count>=1) break;
                    putch('Y');
                    yesorno[count]='Y';
                    count++;
                    break;
            case'n':
            case'N':if(count>=1) break;
                    putch('N');
                    yesorno[count]='N';
                    count++;
                    break;
            case BACK:if(count==0) break;
                      cprintf("\b");
                      putch('\0');
                      cprintf("\b");
                      count--;
                      if(count<=0) count=0;
                      break;
            case ESC:return NULL;
             case '\0':
             case RIGHT:
             case LEFT:
             case DOWN:
             case PGUP:
             case PGDOWN:
             case HOME:
             case END:
             case UP:break;
            default: break;
           }
      }
 yesorno[count]='\0';
 if(yesorno[0]=='\0') goto get;

 return(yesorno);
}



/***************************本程序专门用于输入书名************************/
char* InputBookName()
{

 int key,count=0;
 char *str;
 str=(char*)malloc(MAXBOOKNAMELEN);
get: while((key=get_key())!=ENTER)
      {
        switch(key){
        case BACK:
               if(count==0) continue;               /*当删除完时*/
               cprintf("\b");
               putch('\0');
               cprintf("\b");
               count--;
               if(count<=0) count=0;

               break;
      case ESC: return NULL;
     /*case SPACE:continue;*/
             case '\0':
             case RIGHT:
             case LEFT:
             case DOWN:
             case PGUP:
             case PGDOWN:
             case HOME:
             case END:
             case UP:break;
     default:if(count>MAXBOOKNAMELEN-2) continue;  /*当输入太多时*/
             putch(key);
             str[count]=key;
             count++;
              }
    }
str[count]='\0';
if(str[0]=='\0') goto get;
return(str);
}