如何在MFC中读取txt文件中的数据

MFC主要读写文件的类是CFile,而CStdioFile类是派生自CFile类的，主要增加了一个按行的方式读取/写入文件每行字符串的功能

读写TXT文件，写入和输出必须统一格式

CStdioFile

myFile,

File

if(myFile.Open(CBApp::getCurrModulePath()+_T("filename.txt"),

CFile::modeRead))

{

//读取

myFile.ReadString(str)

myFile.Close()

}

else

{

//创建

File.Open(CBApp::getCurrModulePath()+_T("filename.txt"),

CFile::modeWrite

|

CFile::modeCreate)

File.WriteString(sFileName)

File.Close()

}

//写入

File.Open(CBApp::getCurrModulePath()+_T("filename.txt"),

CFile::modeWrite

)

File.WriteString(sFileName)

File.Close()

//下面的代码是一个实现C++连接MYSQL数据库的很好的例子

//这里用了建表，插入，检索，删表等常用功能

//我用VC++6.0生成，已经成功连接了。

//在VC++6.0中要想把做一下两步准备工作才可以。

//(1)Tools->Options->Directories->Include files中添加C:\Program Files\MySQL\MySQL Server 6.0\include

//(2)Tools->Options->Directories->Library files中添加C:\Program Files\MySQL\MySQL Server 6.0\lib\opt

//其实就是将头文件和库文件包含进来

//我觉得这个例子写的很好，再结合自己的试验，特地介绍给大家！

#include <winsock.h>

#include <iostream>

#include <string>

#include <mysql.h>

using namespace std

#pragma comment(lib, "ws2_32.lib")

#pragma comment(lib, "libmysql.lib")

//单步执行，不想单步执行就注释掉

#define STEPBYSTEP

int main() {

cout <<"****************************************" <<endl

#ifdef STEPBYSTEP

system("pause")

#endif

//必备的一个数据结构

MYSQL mydata

//初始化数据库

if (0 == mysql_library_init(0, NULL, NULL)) {

cout <<"mysql_library_init() succeed" <<endl

} else {

cout <<"mysql_library_init() failed" <<endl

return -1

}

#ifdef STEPBYSTEP

system("pause")

#endif

//初始化数据结构

if (NULL != mysql_init(&mydata)) {

cout <<"mysql_init() succeed" <<endl

} else {

cout <<"mysql_init() failed" <<endl

return -1

}

#ifdef STEPBYSTEP

system("pause")

#endif

//在连接数据库之前，设置额外的连接选项

//可以设置的选项很多，这里设置字符集，否则无法处理中文

if (0 == mysql_options(&mydata, MYSQL_SET_CHARSET_NAME, "gbk")) {

cout <<"mysql_options() succeed" <<endl

} else {

cout <<"mysql_options() failed" <<endl

return -1

}

#ifdef STEPBYSTEP

system("pause")

#endif

//连接数据库

if (NULL

!= mysql_real_connect(&mydata, "localhost", "root", "test", "test",

3306, NULL, 0))

//这里的地址，用户名，密码，端口可以根据自己本地的情况更改

{

cout <<"mysql_real_connect() succeed" <<endl

} else {

cout <<"mysql_real_connect() failed" <<endl

return -1

}

#ifdef STEPBYSTEP

system("pause")

#endif

//sql字符串

string sqlstr

//创建一个表

sqlstr = "CREATE TABLE IF NOT EXISTS user_info"

sqlstr += "("

sqlstr +=

"user_id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY COMMENT 'Unique User ID',"

sqlstr +=

"user_name VARCHAR(100) CHARACTER SET gb2312 COLLATE gb2312_chinese_ci NULL COMMENT 'Name Of User',"

sqlstr +=

"user_second_sum INT UNSIGNED NOT NULL DEFAULT 0 COMMENT 'The Summation Of Using Time'"

sqlstr += ")"

if (0 == mysql_query(&mydata, sqlstr.c_str())) {

cout <<"mysql_query() create table succeed" <<endl

} else {

cout <<"mysql_query() create table failed" <<endl

mysql_close(&mydata)

return -1

}

#ifdef STEPBYSTEP

system("pause")

#endif

//向表中插入数据

sqlstr =

"INSERT INTO user_info(user_name) VALUES('公司名称'),('一级部门'),('二级部门'),('开发小组'),('姓名')"

if (0 == mysql_query(&mydata, sqlstr.c_str())) {

cout <<"mysql_query() insert data succeed" <<endl

} else {

cout <<"mysql_query() insert data failed" <<endl

mysql_close(&mydata)

return -1

}

#ifdef STEPBYSTEP

system("pause")

#endif

//显示刚才插入的数据

sqlstr = "SELECT user_id,user_name,user_second_sum FROM user_info"

MYSQL_RES *result = NULL

if (0 == mysql_query(&mydata, sqlstr.c_str())) {

cout <<"mysql_query() select data succeed" <<endl

//一次性取得数据集

result = mysql_store_result(&mydata)

//取得并打印行数

int rowcount = mysql_num_rows(result)

cout <<"row count: " <<rowcount <<endl

//取得并打印各字段的名称

unsigned int fieldcount = mysql_num_fields(result)

MYSQL_FIELD *field = NULL

for (unsigned int i = 0i <fieldcounti++) {

field = mysql_fetch_field_direct(result, i)

cout <<field->name <<"\t\t"

}

cout <<endl

//打印各行

MYSQL_ROW row = NULL

row = mysql_fetch_row(result)

while (NULL != row) {

for (int i = 0i <fieldcounti++) {

cout <<row[i] <<"\t\t"

}

cout <<endl

row = mysql_fetch_row(result)

}

} else {

cout <<"mysql_query() select data failed" <<endl

mysql_close(&mydata)

return -1

}

#ifdef STEPBYSTEP

system("pause")

#endif

//删除刚才建的表

sqlstr = "DROP TABLE user_info"

if (0 == mysql_query(&mydata, sqlstr.c_str())) {

cout <<"mysql_query() drop table succeed" <<endl

} else {

cout <<"mysql_query() drop table failed" <<endl

mysql_close(&mydata)

return -1

}

mysql_free_result(result)

mysql_close(&mydata)

mysql_server_end()

system("pause")

return 0

}

读文件：

Win32 API：首先CreateFile打开文件，然后ReadFile读取文件，CloseHandle关闭文件句柄

C：1、fopen 2、fread 3、fclose

MFC显示文字：

CDC* pDC = GetDC().

pDC->TextOut()

//或者 pDC->DrawText()

ReleaseDC(pDC)

---