有什麼方法可以方便地爲Winsock send（）生成一個HTTP頭，而不是手動連接一個字符串？

Question

例如，而不是這樣做：

char * buf = "HTTP/1.0 200 OK\r\n..."; 
sendRet = send(ClientSocket, buf, strlen(buf), 0); 

事情是這樣的：

HttpHeader h; 
h.Version = "1.0"; 
h.Status = "200 OK"; 
h.ContentType = HTTP_CONTENT_TYPE_TEXT_XML; 
... 
sendRet = send(ClientSocket, h.ToString(), h.Length(), 0); 

Answer 1

你當然可以創建自己的HttpHeader來處理，但你最終還是不得不建立在HTTP它傳遞給send()之前手動頭，例如：

struct HttpHeader 
{ 
    char *Version; 
    char *Status; 
    char *ContentType; 
}; 

char* HttpHeaderToString(HttpHeader *hdr) 
{ 
    int len = strlen(hdr->Version) + strlen(hdr->Status) + 10; 
    if (strlen(hdr->ContentType) > 0) 
     len += (strlen(hdr->ContentType) + 16); 
    //... 

    char *str = (char*) malloc(len); 
    if (str != NULL) 
    {   
     sprintf(str, "HTTP/%s %s\r\n", hdr->Version, hdr->Status); 
     if (strlen(hdr->ContentType) > 0) 
     { 
      strcat(str, "Content-Type: "); 
      strcat(str, hdr->ContentType); 
      strcat(str, "\r\n"); 
     } 
     //... 
     strcat(str, "\r\n"); 
    } 
    return str; 
} 

HttpHeader h; 
h.Version = "1.0"; 
h.Status = "200 OK"; 
h.ContentType = HTTP_CONTENT_TYPE_TEXT_XML; 
... 
char *str = HttpHeaderToString(&h); 
if (str != NULL) 
{ 
    send(ClientSocket, str, strlen(str), 0); 
    free(str); 
} 

另一方面，TCP是一個字節流，因此您不必在單個呼叫中發送所有內容。您可以撥打send()多次，因爲你需要，如（檢查省略誤差爲簡潔起見）：

void SendHttpHeader(HttpHeader *hdr) 
{ 
    send(ClientSocket, "HTTP/", 5, 0); 
    send(ClientSocket, hdr->Version, strlen(hdr->Version), 0); 
    send(ClientSocket, " ", 1, 0); 
    send(ClientSocket, hdr->Status, strlen(hdr->Status), 0); 
    send(ClientSocket, "\r\n", 2, 0); 
    if (strlen(hdr->ContentType) > 0) 
    { 
     send(ClientSocket, "Content-Type: ", 14, 0); 
     send(ClientSocket, hdr->ContentType, strlen(hdr->ContentType), 0); 
     send(ClientSocket, "\r\n", 2, 0); 
    } 
    //... 
    send(ClientSocket, "\r\n", 2, 0); 
} 

HttpHeader h; 
h.Version = "1.0"; 
h.Status = "200 OK"; 
h.ContentType = HTTP_CONTENT_TYPE_TEXT_XML; 
... 
SendHttpHeader(&h);