本文介绍了用C ++上传图像文件的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我是C ++环境的新手.我尝试将图像文件上传到C ++中的PHP服务器.但是它不会发送完整的文件.只有我上传的图片文件大小为1 KB.
I am new to C++ environment. I try to upload a image file to PHP server in C++. But it does not send the full file. Only I get uploaded image file size is 1 KB.
我在我这样的职位上有一个职位.但是我不知道如何将图像二进制转换为base64字符串.我尝试了另一种解决方案memcpy，它也行不通.
I got a post in SO like mine. But I don't know how to convert image binary to base64 string. I tried with another solution memcpy, it also doesn't work.
我的C ++代码:
#define _CRT_SECURE_NO_DEPRECATE
#include <iostream>
#include <tchar.h>
#include <Urlmon.h>
#pragma comment (lib, "Urlmon.lib")
#include <windows.h>
#include <wininet.h>
#include <iostream>
#include <tchar.h>
#include <stdio.h>
#pragma comment(lib,"wininet.lib")
#define ERROR_OPEN_FILE 10
#define ERROR_MEMORY 11
#define ERROR_SIZE 12
#define ERROR_INTERNET_OPEN 13
#define ERROR_INTERNET_CONN 14
#define ERROR_INTERNET_REQ 15
#define ERROR_INTERNET_SEND 16
using namespace cv;
using namespace std;
int main()
{
// Local variables
static char *filename = "test.jpg"; //Filename to be loaded
static char *filepath = "test.jpg"; //Filename to be loaded
static char *type = "text/jpeg";
static TCHAR hdrs[] = "Content-Type: multipart/form-data; boundary=---------------------------7d82751e2bc0858";
static char boundary[] = "-----------------------------7d82751e2bc0858"; //Header boundary
static char nameForm[] = "uploadedfile"; //Input form name
static char iaddr[] = "server"; //IP address
static char url[] = "uploader.php";
char * buffer; //Buffer containing file + headers
char * content; //Buffer containing file
FILE * pFile; //File pointer
long lSize; //File size
size_t result;
char *pos; // used in the loop
// Open file
pFile = fopen(filepath, "rb");
if (pFile == NULL)
{
printf("ERROR_OPEN_FILE");
getchar();
return ERROR_OPEN_FILE;
}
printf("OPEN_FILE\n");
// obtain file size:
fseek(pFile, 0, SEEK_END);
lSize = ftell(pFile);
rewind(pFile);
// allocate memory to contain the whole file:
content = (char*)malloc(sizeof(char)*lSize);
if (content == NULL)
{
printf("ERROR_MEMORY");
getchar();
return ERROR_OPEN_FILE;
}
printf("MEMORY_ALLOCATED\t \"%d\" \n", lSize);
// copy the file into the buffer:
result = fread(content, 1, lSize, pFile);
rewind (pFile);
if (result != lSize)
{
printf("ERROR_SIZE");
getchar();
return ERROR_OPEN_FILE;
}
printf("SIZE_OK\n");
// terminate
fclose(pFile);
printf("FILE_CLOSE\n");
//allocate memory to contain the whole file + HEADER
buffer = (char*)malloc(sizeof(char)*lSize + 2048);
//print header
sprintf(buffer, "%s\r\nContent-Disposition: form-data; name=\"%s\"; filename=\"%s\"\r\n", boundary, nameForm, filename);
sprintf(buffer, "%sContent-Type: %s\r\n", buffer, type);
//sprintf(buffer, "%sContent-Length: %d\r\n", buffer, lSize);
sprintf(buffer, "%s\r\n%s\r\n", buffer, content);
/**
sprintf(buffer, "%s\r\n", buffer);
memcpy(buffer + strlen(buffer),content,lSize);
sprintf(buffer, "%s\r\n", buffer);
*/
sprintf(buffer, "%s%s--\r\n", buffer, boundary);
//Open internet connection
HINTERNET hSession = InternetOpen("WINDOWS", INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
if (hSession == NULL)
{
printf("ERROR_INTERNET_OPEN");
getchar();
return ERROR_OPEN_FILE;
}
printf("INTERNET_OPENED\n");
HINTERNET hConnect = InternetConnect(hSession, iaddr, INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 1);
if (hConnect == NULL)
{
printf("ERROR_INTERNET_CONN");
getchar();
return ERROR_INTERNET_CONN;
}
printf("INTERNET_CONNECTED\n");
HINTERNET hRequest = HttpOpenRequest(hConnect, (const char*)"POST", _T(url), NULL, NULL, NULL, INTERNET_FLAG_RELOAD, 1);
if (hRequest == NULL)
{
printf("ERROR_INTERNET_REQ");
getchar();
}
printf("INTERNET_REQ_OPEN\n");
BOOL sent = HttpSendRequest(hRequest, hdrs, strlen(hdrs), buffer, strlen(buffer));
if (!sent)
{
printf("ERROR_INTERNET_SEND");
getchar();
return ERROR_INTERNET_CONN;
}
printf("INTERNET_SEND_OK\n");
printf("\r\n%s\r\n",buffer);
//close any valid internet-handles
InternetCloseHandle(hSession);
InternetCloseHandle(hConnect);
InternetCloseHandle(hRequest);
}
输出:
OPEN_FILE
MEMORY_ALLOCATED "44358"
SIZE_OK
FILE_CLOSE
INTERNET_OPENED
INTERNET_CONNECTED
INTERNET_REQ_OPEN
INTERNET_SEND_OK
-----------------------------7d82751e2bc0858
Content-Disposition: form-data; name="uploadedfile"; filename="test.jpg"
Content-Type: text/jpeg
ÿØÿà
-----------------------------7d82751e2bc0858--
谢谢
推荐答案
如果继续使用二进制路由
If you keep to the binary route
//allocate memory to contain the whole file + HEADER
buffer = (char*)malloc(sizeof(char)*lSize + 2048);
int chars=0;
//print header
chars+=sprintf(buffer+chars, "%s\r\nContent-Disposition: form-data; name=\"%s\"; filename=\"%s\"\r\n", boundary, nameForm, filename);
chars+=sprintf(buffer+chars, "Content-Type: %s\r\n", type);
chars+=sprintf(buffer+chars, "Content-Length: %d\r\n", lSize);
chars+=sprintf(buffer+chars, "\r\n");
memcpy(buffer + chars,content,lSize);
chars+=lSize;
chars+=sprintf(buffer+chars, "\r\n");
chars+=sprintf(buffer+chars, "%s--\r\n", boundary);
但是无论如何，我的建议是让您查看实现HTTP通信的许多现有库中的任何一个( libCURL 是一个不错的起点)
But in any case my recommendation is for your to look at any of the many libraries that exists that implements HTTP communication (libCURL is a good place to start)
一些附加说明:
代替
BOOL sent = HttpSendRequest(hRequest, hdrs, strlen(hdrs), buffer, strlen(buffer));
做
BOOL sent = HttpSendRequest(hRequest, hdrs, strlen(hdrs), buffer, chars);
strlen(buffer)将停在第一个空字符处.
as strlen(buffer) will stop at the first null character.
，当您将结果打印到标准输出时，它将被视为字符串..并以第一个null结尾.
and Whent you're printing the result to std out, it will be treated as string.... and end with the first null.
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