（20200501）【C/C++】txt文件數據讀取之fgets和fscanf

參考：

【1】https://blog.csdn.net/daiyutage/article/details/8540932?utm_medium=distribute.pc_relevant.none-task-blog-BlogCommendFromBaidu-1&depth_1-utm_source=distribute.pc_relevant.none-task-blog-BlogCommendFromBaidu-1

【2】https://mp.csdn.net/console/editor/html/105208262

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#define _CRT_SECURE_NO_WARNINGS
#include <iostream>
#include <cstdio>
#include <string>
using namespace std;

//C語言向文件存入數據
void writeFile()
{
	FILE *fp;
	fp = fopen("0501.txt", "w");
	if (!fp)
	{
		printf("文件打開失敗\n");
		return;
	}

	fprintf(fp, "%s\n", "1234hello");
	fprintf(fp, "%s\n", "1234hello");

	fclose(fp);
	printf("數據存儲完成\n");
}

//使用C語言讀取文件
void ReadFile1()
{
	FILE *fp;
	fp = fopen("0501.txt", "r");
	if (!fp)
	{
		printf("文件打開失敗\n");
		return;
	}

	//讀取第一行:fgets
	char str1[20];
	fgets(str1, 10, fp);
	cout << str1 << endl;
	//分解第一行
	char str1_1[20] = { 0 };
	strncpy(str1_1, str1, 4); 
	cout << str1_1 << endl;
	char str1_2[20] = { 0 };
	strncpy(str1_2, str1+4, 5);
	cout << str1_2 << endl;

	//讀取第2行:fscanf
	char str2[20];
	fscanf(fp, "%s", str2);
	cout << str2 << endl;
	char str2_1[20] = { 0 };
	strncpy(str2_1, str2, 4);
	cout << str2_1 << endl;
	char str2_2[20] = { 0 };
	strncpy(str2_2, str2 + 4, 5);
	cout << str2_2 << endl;

	fclose(fp);
	printf("數據讀取完成\n");
}



int main()

{
	writeFile();//使用C語言寫文件
	ReadFile1();//使用C語言讀取文件
	



	return 0;
}