在服务器中,首先获取图像数据的长度,然后通过TCP套接字获取图像数据。如何将长度(以十六进制)转换为十进制,以便我知道应该读取多少图像数据? (例如0x00 0x00 0x17 0xF0到6128字节)将十六进制从套接字转换为十进制
char len[4];
char buf[1024];
int lengthbytes = 0;
int databytes = 0;
int readbytes = 0;
// receive the length of image data
lengthbytes = recv(clientSocket, len, sizeof(len), 0);
// how to convert binary hex data to length in bytes
// get all image data
while (readbytes < ???) {
databytes = recv(clientSocket, buf, sizeof(buf), 0);
FILE *pFile;
pFile = fopen("image.jpg","wb");
fwrite(buf, 1, sizeof(buf), pFile);
readbytes += databytes;
}
fclose(pFile);
编辑:这是工作的。
typedef unsigned __int32 uint32_t; // Required as I'm using Visual Studio 2005
uint32_t len;
char buf[1024];
int lengthbytes = 0;
int databytes = 0;
int readbytes = 0;
FILE *pFile;
pFile = fopen("new.jpg","wb");
// receive the length of image data
lengthbytes = recv(clientSocket, (char *)&len, sizeof(len), 0);
// using networkd endians to convert hexadecimal data to length in bytes
len = ntohl(len);
// get all image data
while (readbytes < len) {
databytes = recv(clientSocket, buf, sizeof(buf), 0);
fwrite(buf, 1, sizeof(buf), pFile);
readbytes += databytes;
}
fclose(pFile);
“二进制十六进制数据”是什么意思?它可以是二进制或十六进制。你在寻找类似'ntohl'的东西吗? **将这4个字节写入流的代码在哪里? – Jon 2013-03-05 11:42:46
@Jon。谢谢! – askingtoomuch 2013-03-05 12:43:37