关于scanf(" %c"&select)与scanf("%c"&select)解决办法

关于scanf(" %c",&select)与scanf("%c",&select)
#include<stdio.h>
#include<stdlib.h>
#include<assert.h>
#include<string.h>
#define N 8

int main(void)
{
typedef struct
{
int num;
char name[18];
char sex[3];
int age;
}StudentType;
StudentType student;
StudentType aStudent[N]=
{
{200301,"张学友","男",43},
{200302,"刘德华","男",42},
{200303,"郭富城","男",45},
{200304,"黎天王","男",41},
{200305,"张靓颖","女",23},
{200306,"李宇春","女",22},
{200307,"窦文涛","男",43},
{200308,"孔夫子","男",36},
};
char fileName[80];
FILE *pFile;
int i;
char select='y';

printf("输入文件名：");
gets(fileName);
if((pFile=fopen(fileName,"wb+"))==NULL)
{
printf("打开文件%s失败！\n""敲任意键退出！\n",fileName);
system("pause");
exit(1);
}
fwrite(&aStudent,sizeof(StudentType),N,pFile);
while(select=='y')
{
rewind(pFile);
printf("输入要显示的学生序号(1~%d):",N);
scanf("%d",&i);
assert(i>=1&&i<=N);
fseek(pFile,sizeof(StudentType)*(i-1),SEEK_CUR);
fread(&student,sizeof(StudentType),1,pFile);
printf("\n学号:%d\n姓名:%s\n性别:%s\n年龄:%d\n\n",student.num,student.name,student.sex,student.age);

printf("是否继续(Y/N):");
scanf("%c",&select);
select=tolower(select);
assert(select=='y'||select=='n');
}
fclose(pFile);
system("pause");
return 0;
}

这里scanf(" %c",&select),如若没有空格即：scanf("%c",&select),程序将会由assert结束
执行结果：
调用scanf()结束：将不会进行输入，直接进行后面的运算，导致assert，退出程序。
新手，呵呵，自己手动调试结果：在调用scanf()前:&select 值：0x0012fe04 "y烫?" select 值： 121 'y'
调用scanf()后：&select 值：0x0012ffe04 "烫?" select 值：10 ''

这里就糊涂了,scanf() 对这种情况为什么会有这种结果，scanf()处理这种情况的详细细节。
新人分不多，求高手解析，拜谢！！

------解决方案--------------------
由于C一般没有把最后一个回车键处理掉，而是停留在缓冲区内。从而导致你scanf的时候获得到了回车键。参考下代码。

C/C++ code


#define N 8

int main(void)
{
    typedef struct
    {
        int num;
        char name[18];
        char sex[3];
        int age;
    }StudentType;
    StudentType student;
    StudentType aStudent[N]=
    {
        {200301,"张学友","男",43},
        {200302,"刘德华","男",42},
        {200303,"郭富城","男",45},
        {200304,"黎天王","男",41},
        {200305,"张靓颖","女",23},
        {200306,"李宇春","女",22},
        {200307,"窦文涛","男",43},
        {200308,"孔夫子","男",36},
    };
    char fileName[80];
    FILE *pFile;
    int i;
    char select='y';

    printf("输入文件名：");
    gets(fileName);
    if((pFile=fopen(fileName,"wb+"))==NULL)
    {
        printf("打开文件%s失败！\n""敲任意键退出！\n",fileName);
        system("pause");
        exit(1);
    }
    fwrite(&aStudent,sizeof(StudentType),N,pFile);
    while(select=='y')
    {
        rewind(pFile);
        printf("输入要显示的学生序号(1~%d):",N);
        scanf("%d",&i);
        getchar();
        assert(i>=1&&i<=N);
        fseek(pFile,sizeof(StudentType)*(i-1),SEEK_CUR);
        fread(&student,sizeof(StudentType),1,pFile);
        printf("\n学号:%d\n姓名:%s\n性别:%s\n年龄:%d\n\n",student.num,student.name,student.sex,student.age);

        printf("是否继续(Y/N):");
        scanf("%c",&select);
        select=tolower(select);
        assert(select=='y'||select=='n');
    }
    fclose(pFile);
    system("pause");
    return 0;
}

关于scanf(" %c"&select)与scanf("%c"&select)解决办法

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