C++操作文件行(读取，删除，修改指定行)

/********************************************************
Copyright (C),  2016-2018,
FileName:main
Author:        woniu201
Email:         wangpengfei.201@163.com
Created:       2018/08/31
Description:文件操作：读取指定行，删除指定行，修改指定行
********************************************************/
#include <iostream>
#include <fstream>
#include <string>
using namespace std;/************************************
@ Brief:读取指定行数据
@ Author:woniu201
@ Created:2018/08/31
@ Return:
************************************/
void ReadLineData(char* fileName, int lineNum, char* data)
{
ifstream in;
in.open(fileName);int line = 1;
while (in.getline(data, 1024))
{
if (lineNum == line)
{
break;
}
line ++ ;
}in.close();
}/************************************
@ Brief:字符串转string类型
@ Author:woniu201
@ Created:2018/08/31
@ Return:
************************************/
string CharToStr(char * contentChar)
{
string tempStr;
for (int i=0;contentChar[i]!='\0';i++)
{
tempStr+=contentChar[i];
}
return tempStr;
}/************************************
@ Brief:删除指定行
@ Author:woniu201
@ Created:2018/08/31
@ Return:
************************************/
void DelLineData(char* fileName, int lineNum)
{
ifstream in;
in.open(fileName);string strFileData = "";
int line = 1;
char lineData[1024] = {0};
while(in.getline(lineData, sizeof(lineData)))
{
if (line == lineNum)
{
strFileData += "\n";
}
else
{
strFileData += CharToStr(lineData);
strFileData += "\n";
}
line++;
}
in.close();//写入文件
ofstream out;
out.open(fileName);
out.flush();
out<<strFileData;
out.close();
}/************************************
@ Brief:        修改行数据
@ Author:woniu201
@ Created:2018/08/31
@ Return:
************************************/
void ModifyLineData(char* fileName, int lineNum, char* lineData)
{
ifstream in;
in.open(fileName);string strFileData = "";
int line = 1;
char tmpLineData[1024] = {0};
while(in.getline(tmpLineData, sizeof(tmpLineData)))
{
if (line == lineNum)
{
strFileData += CharToStr(lineData);
strFileData += "\n";
}
else
{
strFileData += CharToStr(tmpLineData);
strFileData += "\n";
}
line++;
}
in.close();//写入文件
ofstream out;
out.open(fileName);
out.flush();
out<<strFileData;
out.close();
}int main()
{
char lineData[1024] = {0};
ReadLineData("D:\\project\\cpp\\2010\\jsondemo\\jsondemo\\1.json", 21, lineData);
cout << lineData << endl;DelLineData("D:\\project\\cpp\\2010\\jsondemo\\jsondemo\\1.json", 10);ModifyLineData("D:\\project\\cpp\\2010\\jsondemo\\jsondemo\\1.json", 10, "aaaaaaaaaaaaaa");
getchar();
}

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