/* modnum.c ：修改員工工資記錄        */
#include "stdio.h"
void ModifyByNumber()
 {
    int i,j,k;
    long modnum;    /*存儲管理員輸入的要修改的員工序號*/
    /*輸入各項修改后信息*/
    long Number;
    char Name[20];
    float gongzi;
    float jiangjin;
    float baoxian;
    float shuijin;
    float heji;
    yuangong TmpS;   /*定義進行操作時的臨時結構體變量*/
    yuangong s[SIZE];/*SIZE，在shead.h頭文件中定義的常量，值為100  */
    int recNumber;
    char DataFile[40] = "",next;
    /*DataFile存儲員工工資信息的文件名，next為是否進行下一次刪除操作的選項*/
    FILE *fp;/*====fp指針指向存儲數據的文件名====*/
    /*提示管理員輸入要進行修改記錄的文件名*/
    printf("\nplease input the name of file where data is stored,end with enter key.\n");
    gets(DataFile);
    /*提示管理員輸入要進行修改記錄的文件名*/
    while(*DataFile == ('\0'))
    {
        printf("\nplease input the name of file where data is stored,end with enter key.\n");
        gets(DataFile);
    }
begin:
    /*以讀的方式打開文件，如文件不存在，提示錯誤*/
    fp=fopen(DataFile,"rb");
    if (fp == NULL)
    {
        printf("\nOpen file %s fail!End with any key\n",DataFile);
        perror("Open file fail");
        getch();
        exit(1);
    }
    printf("please input the Employee'seatnum which you will modify:");
    scanf("%ld",&modnum);
    printf("the yuangong you will delete is:%ld\n",modnum);
    /*輸入要修改記錄的各項內容值*/
    Number=modnum;
    printf("name=");
    scanf("%s",Name);

    printf("gongzi=");
    scanf("%f",&gongzi);

    printf("jiangjin=");
    scanf("%f",&jiangjin);

    printf("baoxian=");
    scanf("%f",&baoxian);

    printf("shuijin=");
    scanf("%f",&shuijin);

    /*用公式自動計算員工實發工資即合計*/
    heji=gongzi+jiangjin-baoxian-shuijin;
   /*將文件中要修改的信息存入結構體數組*/
   recNumber=0;
   /*循環將文件數據讀入結構體數組，
   如文件中的數據員工號和要修改的員工號不符，則原樣寫入數組，
   如文件中數據的員工號和要修改員工號匹配，
   則根據管理員輸入的各項修改內容重新賦值，即修改，并寫入數組*/
    while((fread(&TmpS,sizeof(yuangong),1,fp)) != (int)NULL)
    {
        if(TmpS.Number!=modnum)
            {
            s[recNumber].Number = TmpS.Number;
            strcpy(s[recNumber].Name, TmpS.Name);
            s[recNumber].gongzi = TmpS.gongzi;
            s[recNumber].jiangjin = TmpS.jiangjin;
            s[recNumber].baoxian = TmpS.baoxian;
            s[recNumber].shuijin = TmpS.shuijin;
            s[recNumber].heji = TmpS.heji;
            recNumber++;
            }
        else
            {
            s[recNumber].Number = Number;
            strcpy(s[recNumber].Name, Name);
            s[recNumber].gongzi = gongzi;
            s[recNumber].jiangjin = jiangjin;
            s[recNumber].baoxian = baoxian;
            s[recNumber].shuijin = shuijin;
            s[recNumber].heji = heji;
            recNumber++;
            }
    }
    fclose(fp);
   /*====將修改后的結構體數組記錄寫入文件====*/
        fp=fopen(DataFile,"wb+");
        if (fp == NULL)
        {
            printf("\nSet up file %sfail !end with anykey.\n",DataFile);
            perror("Set up fail");
            getch();
            exit(1);
        }
        for(i=0; i<recNumber; i++)
        {
            if(fwrite(&s[i],sizeof(yuangong),1,fp)!=1)
            {
                printf("\nWrite file %s fail!end with anykey.\n",DataFile);
                perror("Write file fail!");
                    getch();
                    exit(1);
            }
        }
        fclose(fp);
     /*====顯示修改后的文件====*/
    fp=fopen(DataFile,"rb");
    if (fp == NULL)
    {
        printf("\nOpen file%sfail!End with any key \n",DataFile);
        perror("Open file fail");
        getch();
        exit(1);
    }
    printf("the file after modify is:\n");
    printf("\nNumber \t\tName\tgongzi\tjiangjin\tbaoxian\n");
    while(fread(&TmpS,sizeof(yuangong),1,fp) != (int)NULL)
    {
        if(TmpS.Number!=0)
        printf("\n%ld\t        %s\t   %5.2f\t  %5.2f\t         %5.2f\t%5.2f\t%5.2f\n",TmpS.Number,TmpS.Name,TmpS.gongzi,TmpS.jiangjin,TmpS.baoxian,TmpS.shuijin,TmpS.heji);
    }
    fclose(fp);
/*提示是否進行下一次修改*/
    printf("\nGo on ?(y/n)");
    next=getche();
    putchar('\n');
    if ( next =='y' || next =='Y') goto begin;
 }