关于NSInputstream

Question

-(NSString*)dateFilePath{

NSArray *paths=NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

NSString *documentsDirectory=[paths objectAtIndex:0];

return [documentsDirectory stringByAppendingPathComponent:kFileName];
}


- (void)viewDidLoad
{

int actuallyRead=0;

NSString *path=[self dateFilePath];

NSURL *audiourl=[[NSURL alloc]initFileURLWithPath:path];

NSLog(@"%@",audiourl);

inStream=[[NSInputStream alloc]initWithURL:audiourl];

actuallyRead=[inStream read:buffer maxLength:sizeof(buffer)];

NSLog(@"%d",actuallyRead);

[dataBuffer1 appendBytes:buffer length:actuallyRead];

NSLog(@"%d",actuallyRead);

[inStream release];

[super viewDidLoad];

}
IN .h file
NSInputStream  *inStream;
NSMutableData  *dateBuffer1;
unint8_t       buffer[1024];

在Documents中的一个文件中，我想使用此方法加载到缓冲区中，但actuallyRead总是-1，我的方法中有错误吗？

Answer 1

您总是得到-1的原因是您忘记打开流，所以您所要做的就是在初始化NSInputStream之后尝试读取它之前插入行[inStream open];。

Answer 2

您应该通过以下方式检查inStream是否可用

if (nil == inStream)