iOS 程式在UITextView中顯示NSLog日誌的方法，

標籤：

 最近開發程式，需要做個給測試人員的demo，用戶端可以即時 顯示程式的列印日誌的功能，

尋找了很多的資料找到個方法，利用NSPipe即可以實現，

蘋果官方解釋：

      objects provide an object-oriented interface for accessing pipes. An NSPipe object represents both ends of a pipe and enables communication through the pipe. A pipe is a one-way communications channel between related processes; one process writes data, while the other process reads that data. The data that passes through the pipe is buffered; the size of the buffer is determined by the underlying operating system.NSPipe is an abstract class, the public interface of a class cluster.

   NSPipe是一個抽象類別，一類叢集的公用介面。通過NSPipe 我們可以方便的讀取和寫入進程資料，

如果想實現將 程式的即時日誌列印，可以在控制器中添加下邊方法

- (void)redirectNotificationHandle:(NSNotification *)nf{ // 通知方法    NSData *data = [[nf userInfo] objectForKey:NSFileHandleNotificationDataItem];    NSString *str = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];        self.logTextView.text = [NSString stringWithFormat:@"%@\n\n%@",self.logTextView.text, str];// logTextView 就是要將日誌輸出的視圖（UITextView）    NSRange range;    range.location = [self.logTextView.text length] - 1;    range.length = 0;    [self.logTextView scrollRangeToVisible:range];    [[nf object] readInBackgroundAndNotify];}- (void)redirectSTD:(int )fd{     NSPipe * pipe = [NSPipe pipe] ;// 初始化一個NSPipe 對象    NSFileHandle *pipeReadHandle = [pipe fileHandleForReading] ;    dup2([[pipe fileHandleForWriting] fileDescriptor], fd) ;        [[NSNotificationCenter defaultCenter] addObserver:self                                             selector:@selector(redirectNotificationHandle:)                                                 name:NSFileHandleReadCompletionNotification                                               object:pipeReadHandle]; // 註冊通知    [pipeReadHandle readInBackgroundAndNotify];}

執行

 [self redirectSTD:STDOUT_FILENO];

    [self redirectSTD:STDERR_FILENO];

就可以實現輸出列印，

 

　　

 

iOS 程式在UITextView中顯示NSLog日誌的方法，