使用C++发送使用http POST的文件

Question

#include <winsock2.h> 
#include <windows.h> 
#include <iostream> 
#pragma comment(lib,"ws2_32.lib") 
using namespace std; 
int main(){ 
    WSADATA wsaData; 
    if (WSAStartup(MAKEWORD(2,2), &wsaData) != 0) { 
     cout << "WSAStartup failed.\n"; 
     system("pause"); 
     return 1; 
    } 
    SOCKET Socket=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP); 
    struct hostent *host; 
    host = gethostbyname("127.0.0.1"); 
    SOCKADDR_IN SockAddr; 
    SockAddr.sin_port=htons(80); 
    SockAddr.sin_family=AF_INET; 
    SockAddr.sin_addr.s_addr = *((unsigned long*)host->h_addr); 
    cout << "Connecting...\n"; 
    if(connect(Socket,(SOCKADDR*)(&SockAddr),sizeof(SockAddr)) != 0){ 
     cout << "Could not connect"; 
     system("pause"); 
     return 1; 
    } 
    cout << "Connected.\n"; 



      char header[]="POST /xampp/tests/file/check.php HTTP/1.1\r\n" 
       "Host: 127.0.0.1\r\n" 
       "Content-Type: application/x-www-form-urlencoded\r\n" 
       "Content-Length: 10\r\n" 
       "Connection: close\r\n" 
       "\r\n" 
       "text1=sase"; 
    send(Socket,header, strlen(header),0); 
    char buffer[100000]; 
    int nDataLength; 
    while ((nDataLength = recv(Socket,buffer,100000,0)) > 0){   
     int i = 0; 
     while (buffer[i] >= 32 || buffer[i] == '\n' || buffer[i] == '\r') { 
      cout << buffer[i]; 
      i += 1; 
     } 
    } 
    closesocket(Socket); 
     WSACleanup(); 
     cout<<endl<<endl; 
    system("pause"); 
    return 0; 
} 

这是我当前的代码。它发送text1，但现在我想要它发送一个文件（位于：C：\ Users \ Wade \ Downloads \ Documents）。我该怎么做 如何使用HTTP POST协议将用户的文件发送到服务器

Answer 1

application/x-www-form-urlencoded只支持name=value对。要POST一个文件，你必须要么：

1. 使用multipart/form-data代替。

   char *header="POST /xampp/tests/file/check.php HTTP/1.1\r\n" 
        "Host: 127.0.0.1\r\n" 
        "Content-Type: multipart/form-data; boundary=myboundary\r\n" 
        "Connection: close\r\n" 
        "\r\n" 
        "--myboundary\r\n" 
        "Content-Type: application/octet-stream\r\n" 
        "Content-Disposition: form-data; name=\"myfile\"; filename=\"myfile.ext\"\r\n" 
        "Content-Transfer-Encoding: 8bit\r\n" 
        "\r\n"; 
   send(Socket,header, strlen(header),0); 
   
   // send the raw file bytes here... 
   
   char *footer = "\r\n" 
         "--myboundary--\r\n"; 
   send(Socket, footer, strlen(footer), 0); 
   

2. 通过自身发送文件的内容作为整个POST内容，设置Content-Type到的实际类型的文件或application/octet-stream的，并设置Content-Length到文件的大小。

   char *header="POST /xampp/tests/file/check.php HTTP/1.1\r\n" 
        "Host: 127.0.0.1\r\n" 
        "Content-Type: application/octet-stream\r\n" 
        "Content-Length: ...\r\n" // <-- substitute with the actual file size 
        "Connection: close\r\n" 
        "\r\n"; 
   send(Socket,header, strlen(header),0); 
   
   // send the raw file bytes here... 
   

你使用哪一个取决于什么服务器是能够接受的。

Answer 2

我去工作。这里是没有读取文件的代码。

char outtemp[]; 
    ifstream inFile("c:\\temp.html"); 
    ofstream outtemp("temp"); 
    while(inFile.good()){ 
          getline(inFile,buffer); 
          outtemp<<buffer; 
          } 
    inFile.close();//close files after using 
    outtemp.close();//close files after using 




    char data[]= 
    "\r\n" 
    "--border287032381131322\r\n" 
    "Content-Disposition: form-data; name=\"this\" \r\n\r\n" 
    "aasda\r\n\r\n" 
    "--border287032381131322\r\n" 
    "Content-Disposition: form-data; name=\"file\"; filename=\"C:\\temp.html\" Content-Type: text/plain \r\n\r\n" 
char data2[]= 
    "<h1>Home page on main server</h1>\r\n\r\n" 
    "--border287032381131322--\r\n"; 

    char header[] = 
    "POST /xampp/tests/winsock_test/do.php HTTP/1.1\r\n" 
    "Host: 127.0.0.1\r\n" 
    "Content-Type: multipart/form-data; boundary=border287032381131322\r\n" 
    "Connection: close\r\n"; 
    strcat(header,data1); 
strcat(header,outtemp); 
strcat(header,data2) 
    cout<<"----------Sending----------------"<<endl<<header<<endl<<"size:"<<sizeof(data)<<endl<<"--------------sending end------------"<<endl<<endl;// for debug 

    send(Socket,header, strlen(header),0); 

Answer 3

使用此代码

#define DATA_SIZE 1024*1024*10 //10MB 
#define MAXLINE 409600 

char * servIP = "127.0.0.1"; 
int servPort = 80; 

ssize_t send_file(char *fileDir, char *filename) 
{ 
    char *packet; 
    char pre_body[1024], post_body[1024]; 
    char sendline[MAXLINE + 1]; 
    char boundary[] ="----WebKitFormBoundaryu8FzpUGNDgydoA4z"; 

    char *bodyline = calloc(sizeof(char), DATA_SIZE); 
    char *fileBuf = calloc(sizeof(char), DATA_SIZE); 
    int sock = makeSocket(); 

    printf("send file name : %s\n", filename); 

    FILE *fp = fopen(fileDir, "r"); 
    if(fp == NULL){ 
     printf("file can't read\n"); 
     fclose(fp); 
     return -1; 
    } 

    fseek(fp, 0, SEEK_END); 
    int file_size = ftell(fp); 
    fseek(fp, 0, SEEK_SET); 
    if(fread(fileBuf, 1, file_size, fp) == -1){ 
     printf("fread error\n"); 
    } 
    // make body 
    sprintf(pre_body, "--%s\r\nContent-Disposition: form-data; name=\"pdata\"\r\n\r\n" 
     "%s\r\n--%s\r\nContent-Disposition: form-data; name=\"flag\"\r\n\r\n" 
     "%s\r\n--%s\r\nContent-Disposition: form-data; name=\"upfile\";filename=\"%s\"\r\n" 
     "Content-Type:application/octect-stream\r\n\r\n" 
     , boundary, "postdata", boundary,"no", boundary, filename); 

    sprintf(post_body, "\r\n--%s--\r\n", boundary); 

    int pre_len = strlen(pre_body); 
    int post_len = strlen(post_body); 
    int body_len = pre_len + file_size + post_len; 

    memcpy(bodyline, pre_body, pre_len); 
    memcpy(bodyline+pre_len, fileBuf, file_size); 
    memcpy(bodyline+pre_len+file_size, post_body, post_len); 

    //make header 
    sprintf(sendline, "POST /FileUpload.jsp HTTP/1.1\r\n" 
     "Host: %s\r\nConnection: keep-alive\r\n" 
     "Content-Length: %d\r\n" 
     "Content-Type: multipart/form-data; boundary=%s\r\n\r\n", servIP, body_len, boundary); 
    int head_len = strlen(sendline); 
    int packet_len = head_len+body_len; 

    //join header + body 
    packet=calloc(1, head_len+body_len+1); 
    memcpy(packet, sendline, head_len); 
    memcpy(packet+head_len, bodyline, body_len); 


    write(sock, packet, packet_len); 

    fclose(fp); 
    free(packet); 
    close(sock); 
    return 0; 
} 

int makeSocket(){ 
    struct sockaddr_in servAddr; 
    int sock; 
    char ip[20]; 
    /* Create areliable, stream socket using TCP */ 
    if((sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) 
     printf("socket create failed\n"); 

    struct hostent *host_entry; 
    host_entry = gethostbyname(servIP); 
    for(ndx = 0; NULL != host_entry->h_addr_list[ndx]; ndx++){ 
     strcpy(ip, inet_ntoa(*(struct in_addr*)host_entry->h_addr_list[ndx])); 
    } 

    memset(&servAddr, 0, sizeof(servAddr)); //Zero ou structure 
    servAddr.sin_family = AF_INET; //Internet address family 
    servAddr.sin_addr.s_addr = inet_addr(ip); //Server IP address 
    servAddr.sin_port = htons(servPort);//Server port 

    /* Establish the connection to the web server */ 
    if(connect(sock, (struct sockaddr *) &servAddr, sizeof(servAddr)) < 0) 
      printf("connet() failed\n"); 

    return sock; 
}