c++ - Why is the beginning of my string disappearing? -

-

In the following C ++ code, I realized that gcount () Was wanting back, because getline () consumes the character of the new line but does not send it to the input stream.

Whatever I did not understand is the output of the program, though. "Test \ n" For input, why do I get "Est \ n"? How does my mistake affect the first character of the string instead of adding unwanted nonsense on the end? And how does the output of the program appear in the debugger ("Test \ n", as I expected), how does it come to the barriers? 

  #include & lt; Fstream & gt; #include & lt; Vector & gt; #include & lt; String & gt; # Include & lt; Iostream & gt; using namespace std; Int main () {int buffer size = 1024; Ifstream input ("test.txt", iOS :: in | iOS :: binary); Of vector & lt; Four & gt; Wakebuffer (buffer size); Input.gateline (& vecBuffer [0], buffer size); String Strass (vecBuffer.begin (), vecBuffer.begin () + input.gcount ()); Cout & lt; & Lt; StrResult & lt; & Lt; "\ N"; Return 0; } I have also repeated this result, Windows Vista, Visual Studio 2005 SP2   
 
 
 When I think what the heck is happening, then I will update this post.  
  Edit : Okay, we go there. Problems (and different results are getting people) are from \ r. What happens when you call  input.getline  and put the result in vecBuffer. The gateline function closes \ n strips, but leaves \ r in place. 
 
 Then you transfer the wiffer to the string variable, but use the gateout function from the input, which means that you will get a lot four because the input variable is still \ n included, and VecBuffer does not 
 
 The resulting strasselt is: 
 
  - strResult "test" [0] 84 't' four [1] 101 'e' four [2] 115 'four' [3] 116 't' four [4] 13 '␍' four [four] [four] [four]  
 
 Then the "test" is printed, followed by Carris Return ( Cursor back in the beginning of the line), a blank character (written on T), and finally \ n, who correctly puts the cursor on the new line. 
 
 Then you must either remove \ r, or write a function that checks the length of the string directly from the Wakebuffer, blank characters.

Comments

Post a Comment

Popular posts from this blog

c++ - Linux and clipboard -

-
After selecting the copies of the buffer in Linux, after the text, we can click and paste the button between the mouse. I think there is a special buffer for this, I want to use it. Programming Language: C ++ Your Library: Qt Thanks. There is just one more correct answer than Paul Dixon, which answers your needs: / P > QClipboard * clipboard = QApplication :: clipboard (); CastString Selected Text = Clipboard-> Text (QClipboard :: Selection);
Read more

Visual Studio 2005: How to speed up builds when a VSMDI is open? -

-
Using Visual Studio 2005, if I open the test in VSMFI and try to run the tests, then sometimes the projects are ready. However, they run very slow. CPU 99% waste and output window VS Shows things associated with compiling it. Is there any way to fix this? It does not make any sense. It is not necessary to upgrade that we are a viable alternative to those people who have to deal with the legacy code. Did you try to upgrade SP1? I do not know of any specific problem in this area, but this will be the first change I tried to do.
Read more

booting ubuntu from usb using virtualbox -

-
I am trying to install Ubuntu on a USB, the problem is that I do not want to repeat the boot once, I want to keep my windows, but I want to boot Ubuntu using the virtualbox and USB to the Ubuntu Want to use my hard drive, but how? The virtualbox will not recognize USB as a hard drive when installing an ISO In virtualbox, you have to create a virtual hard disk. Make a USB drive and tell the virtual box to install a virtual hard drive that you just created. EDIT: To answer some more questions: In the new Virtual Disk dialog, click the button next to the location field, click on the button Virtual Disk on Flash Drive To access, click the arrow next to Save in the Select File in the window next to Save In, and you can access your flash drive from there. I recommend setting the image to be allocated dynamically, because the size of your flash drive is not available disk space. I name the image, then select that image to install Ubuntu in the Verbill box. The virtualbox will never
Read more