我正在对 iPhone 上的客户端进行编程。我想发送一些字符串，并从服务器接收图像。
我找到了这个教程(http://www.devx.com/wireless/Article/43551)，它非常有用。如果我想接收字符串，它可以工作，但现在我想接收图像，但无法使其工作。
这是我在 iPhone 接收数据时的代码。这是本教程和 JeremyP (http://stackoverflow.com/questions/4613218) 的这个答案的混合:
- (void)stream:(NSStream *)stream handleEvent:(NSStreamEvent)eventCode {
switch(eventCode) {
case NSStreamEventHasBytesAvailable: {
if (data == nil) {
data = [[NSMutableData alloc] init];
}
uint8_t buf[102400];
unsigned int len = 0;
len = [(NSInputStream *)stream read:buf maxLength:102400];
if(len) {
[data appendBytes:(const void *)buf length:len];
// Recibir img
uint8_t size; // Let's make sure size is an explicit width.
NSInteger totalBytesRead = 0;
NSInteger bytesRead = [iStream read: &size maxLength: sizeof size];
while (bytesRead > 0 && totalBytesRead + bytesRead < sizeof size) {
totalBytesRead+= bytesRead;
bytesRead = [iStream read: &size + totalBytesRead maxLength: (sizeof size) - totalBytesRead];
}
if (bytesRead >= 0) {
totalBytesRead += bytesRead;
}
else {
// read failure, report error and bail
}
if (totalBytesRead < sizeof size) {
// connection closed before we got the whole size, report and bail
}
size = ntohl(size); // assume wire protocol uses network byte ordering
NSMutableData* buffer = [[NSMutableData alloc] initWithLength: size];
totalBytesRead = 0;
bytesRead = [iStream read: [buffer mutableBytes] maxLength: size];
while (bytesRead > 0 && totalBytesRead + bytesRead < size) {
totalBytesRead+= bytesRead;
bytesRead = [iStream read: [buffer mutableBytes] + totalBytesRead maxLength: size - totalBytesRead];
}
if (bytesRead >= 0) {
totalBytesRead += bytesRead;
}
else {
// read failure, report error and bail (not forgetting to release buffer)
}
if (totalBytesRead < size) {
// connection closed before we got the whole image, report and bail (not forgetting to release buffer)
}
else {
[buffer setLength: size];
}
imgResultado.image = [UIImage imageWithData: buffer];
[buffer release];
[data release];
data = nil;
}
else {
NSLog(@"No data.");
}
} break;
}}
它不起作用……你能帮我吗？
最佳答案
好吧，我是这样做的，但我不确定是否有更好的方法。
- (void)stream:(NSStream *)stream handleEvent:(NSStreamEvent)eventCode {
switch(eventCode) {
case NSStreamEventHasBytesAvailable:
{
uint32_t max_size = 1000000; // Max size of the received imaged.
NSMutableData* buffer = [[NSMutableData alloc] initWithLength: max_size];
NSInteger totalBytesRead = 0;
NSInteger bytesRead = [(NSInputStream *)stream read: [buffer mutableBytes] maxLength: max_size];
if (bytesRead != 0) {
while (bytesRead > 0 && totalBytesRead + bytesRead < max_size) {
totalBytesRead+= bytesRead;
bytesRead = [(NSInputStream *)stream read: [buffer mutableBytes] + totalBytesRead maxLength: max_size - totalBytesRead];
}
if (bytesRead >= 0) {
totalBytesRead += bytesRead;
}
else {
// read failure, report error and bail (not forgetting to release buffer)
}
[buffer setLength: totalBytesRead];
imgResultado.image = [UIImage imageWithData: buffer];
[buffer release];
}
} break;
}}
使用这种方法，接收到的图像必须小于 max_size。
如果你知道更好的方法来做到这一点，请告诉我! ;)
关于iphone - 在 iPhone 上接收图像(TCP 客户端)，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/9447815/