Fgets使用以前一定要清除键盘缓冲区 fflush(stdin)

#include

#include

#include

 

void inputData (FILE *fPtr);

void updateData (FILE *fPtr);

void delData (FILE *fPtr);

void printData (FILE *fPtr);

int exist ( int num,FILE *fPtr); /*determine if the rec exist*/

int choice (void);

 

struct hardWareData

{

    int recNum;

    char toolName[30];

    int toolNum;

    double toolCost;

};

 

int main ( void )

{

    int choose;

    FILE *fPtr;

 

    if( (fPtr=fopen("client.dat","rb++"))==NULL)

        printf("File not exist\n");

    else

    {

        while ( (choose=choice() )!=5)

        {

            switch (choose)

            {

                case 1:

                inputData(fPtr);

                break;

                case 2:

                updateData(fPtr);

                break;

                case 3:

                delData(fPtr);

                break;

                case 4:

                printData(fPtr);

                break;

                default:

                printf("Please input correct number!\n\n");

            }

        }

        fclose(fPtr);

    }

}

 

int choice(void)

{

    int choose;

    printf("1 - Input New Data in \"client.dat\".\n"

         "2 - Update record\n"

         "3 - Delete record\n"

         "4 - Print records\n"

         "5 - Exit\n? ");

 

    scanf ("%d",&choose);

    return choose;

}

 

void inputData(FILE *fPtr)

{

    int newRec;

    struct hardWareData hardWare={ 0, "", 0, 0.00};

    char a[100]={0};

    

    printf("Enter New Record Number:\n? ");

    scanf("%d", &newRec);

    

    if( exist(newRec,fPtr) )

    {

        printf("The record has already exist.Use \"Update Record\"\n");

    }

    else

    {

        hardWare.recNum=newRec;

        

        printf("\n***Enter toolName toolNum toolCost:\n? ");

        fflush(stdin); //如果这里不写，那么gets(a)将直接跳过！！！！

        gets(a);

        sscanf(a,"%[^0-9]%d%lf",hardWare.toolName, &hardWare.toolNum, &hardWare.toolCost);

        

        fseek(fPtr, (newRec-1) * sizeof( struct hardWareData), SEEK_SET);

        fwrite( &hardWare, sizeof( struct hardWareData), 1, fPtr);

    }

}

void updateData(FILE *fPtr)

{

    int upNum;

    struct hardWareData hardWare= {0, "", 0, 0.00};

 

    printf("Enter Update Recourd Number:\n? ");

    scanf("%d", &upNum);

 

    if(!exist(upNum,fPtr))

    {

        printf("The record do not exist.Use \"Input Data\"\n");

    }

    else

    {

        fseek( fPtr,(upNum - 1) *sizeof (struct hardWareData), SEEK_SET);

        fread( &hardWare,sizeof(struct hardWareData),1,fPtr);

        printf("The current data is :/n");

        hardWare.recNum = upNum;

        printf("\n%-5d%-15s%-8d%.2lf\n\n",hardWare.recNum,hardWare.toolName,hardWare.toolNum,hardWare.toolCost);

        printf("Enter New ToolName TollNum ToolCost:\n? ");

 

 

        scanf("%s%d%lf",hardWare.toolName, &hardWare.toolNum, &hardWare.toolCost);

 

        fseek( fPtr,(upNum - 1) *sizeof (struct hardWareData), SEEK_SET);

        fwrite( &hardWare,sizeof(struct hardWareData),1,fPtr);

    }

}

 

void delData(FILE *fPtr)

{

    int delNum;

    struct hardWareData empty={0,"",0,0.00};

 

    printf("Enter the record to delete.\n? ");

    scanf("%d", &delNum);

    

    if(!exist(delNum,fPtr))

    {

        printf("Record do not exist!\n");

    }

    else

    {

        fseek(fPtr,(delNum-1) * sizeof (struct hardWareData), SEEK_SET);

        fwrite(∅, sizeof(struct hardWareData),1,fPtr);

    }

 

}

void printData(FILE *fPtr)

{

    struct hardWareData H={0,"",0,0.00};

    int verify=0;

 

    rewind(fPtr);

 

    printf("\n\n*****************************************\n");

    while (!feof(fPtr))

    {    

        fread( &H,sizeof(struct hardWareData), 1 , fPtr);

        if(verify!=H.recNum && H.recNum !=0)

        {

            printf("%-5d%-15s%-8d%.2lf\n",H.recNum,H.toolName,H.toolNum,H.toolCost);

            verify=H.recNum;

        }

    }

    printf("*****************************************\n\n");

    }

int exist (int num,FILE *fPtr)

{

    struct hardWareData hardWare={0,"",0,0.00};

 

    fseek(fPtr, (num - 1) * sizeof( struct hardWareData), SEEK_SET);

 

    fread(&hardWare, sizeof(struct hardWareData), 1, fPtr);

 

    if (hardWare.recNum == 0)

        return 0;

    else

        return 1;

}