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Read and write in file

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  • _ _AnsHUMAN_

    CStdioFile::ReadString CStdioFile::WriteString

    Somethings seem HARD to do, until we know how to do them. ;-)_AnShUmAn_

    P Offline
    P Offline
    polopo
    wrote on last edited by
    #4

    i try both example but nothing is write in file..File is open but data is not write there? Plz help me

    singh

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    • P polopo

      i try both example but nothing is write in file..File is open but data is not write there? Plz help me

      singh

      T Offline
      T Offline
      toxcct
      wrote on last edited by
      #5

      show your code dude !

      [VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

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      • _ _AnsHUMAN_

        CStdioFile::ReadString CStdioFile::WriteString

        Somethings seem HARD to do, until we know how to do them. ;-)_AnShUmAn_

        P Offline
        P Offline
        polopo
        wrote on last edited by
        #6

        Thx's all I was wrong.. It's working.. THx's for help

        singh

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        • T toxcct

          show your code dude !

          [VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

          C Offline
          C Offline
          cpvc
          wrote on last edited by
          #7

          Hi I more problem when new is came then old line is delete.But i don't want to delete old line..Plz help me

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          • C cpvc

            Hi I more problem when new is came then old line is delete.But i don't want to delete old line..Plz help me

            T Offline
            T Offline
            toxcct
            wrote on last edited by
            #8

            cpvc++ wrote:

            Plz help me

            F*CK, you don't reply to my questions, and still you're asking for help ?!!! :mad:

            [VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

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            • T toxcct

              cpvc++ wrote:

              Plz help me

              F*CK, you don't reply to my questions, and still you're asking for help ?!!! :mad:

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              C Offline
              cpvc
              wrote on last edited by
              #9

              Hey what question Man?I am asking first time..

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              • C cpvc

                Hey what question Man?I am asking first time..

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                T Offline
                toxcct
                wrote on last edited by
                #10

                Does this post mean something to you ?[^]

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                • T toxcct

                  Does this post mean something to you ?[^]

                  [VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

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                  cpvc
                  wrote on last edited by
                  #11

                  Mr. toxcct

                  I am not Mr. polop which is start this thread.I am different user and it's post help me and i want some more help me..Sorry for missunderstanding any way my code is here..Pla help me

                  CStdioFile file;
                  if (file.Open("\\log.txt", CFile::modeCreate|CFile::modeWrite ))
                  {
                  file.WriteString(logfile);

                  	file.WriteString("\\n");
                  	
                  }
                  file.Close();
                  

                  logfile is CString type which have some information.. Now i am able to write in file but old line is delete when new line write. Plz help me

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                  • C cpvc

                    Mr. toxcct

                    I am not Mr. polop which is start this thread.I am different user and it's post help me and i want some more help me..Sorry for missunderstanding any way my code is here..Pla help me

                    CStdioFile file;
                    if (file.Open("\\log.txt", CFile::modeCreate|CFile::modeWrite ))
                    {
                    file.WriteString(logfile);

                    	file.WriteString("\\n");
                    	
                    }
                    file.Close();
                    

                    logfile is CString type which have some information.. Now i am able to write in file but old line is delete when new line write. Plz help me

                    T Offline
                    T Offline
                    toxcct
                    wrote on last edited by
                    #12

                    cpvc++ wrote:

                    I am not Mr. polop which is start this thread

                    sorry, I didn't notice that aspect of the things :) The problem in your code is that you're using CFile::modeCreate, but according to the documentation[^], this flag tells to truncate the file if already existing :

                    MSDN says:

                    CFile::modeCreate Directs the constructor to create a new file. If the file exists already, it is truncated to 0 length

                    So, you have to add the flag CFile::modeNoTruncate to counter this undesired behavior. The use of this flag however keeps the file pointer at the beginning of the file. So if you want to append things at the end, you must call once after CStdioFile::Open() the function CStdioFile::Seek(CFile::end). Does the following work better ?

                    CStdioFile file;
                    if (file.Open(_T("\\log.txt"), CFile::modeCreate | CFile::modeWrite | CFile::modeNoTruncate)) {
                    //file.Seek(0, CFile::end);
                    file.SeekToEnd();
                    file.WriteString(logfile);
                    file.WriteString(_T("\n"));
                    file.Close();
                    }

                    [VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

                    modified on Thursday, September 4, 2008 6:46 AM

                    C 1 Reply Last reply
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                    • T toxcct

                      cpvc++ wrote:

                      I am not Mr. polop which is start this thread

                      sorry, I didn't notice that aspect of the things :) The problem in your code is that you're using CFile::modeCreate, but according to the documentation[^], this flag tells to truncate the file if already existing :

                      MSDN says:

                      CFile::modeCreate Directs the constructor to create a new file. If the file exists already, it is truncated to 0 length

                      So, you have to add the flag CFile::modeNoTruncate to counter this undesired behavior. The use of this flag however keeps the file pointer at the beginning of the file. So if you want to append things at the end, you must call once after CStdioFile::Open() the function CStdioFile::Seek(CFile::end). Does the following work better ?

                      CStdioFile file;
                      if (file.Open(_T("\\log.txt"), CFile::modeCreate | CFile::modeWrite | CFile::modeNoTruncate)) {
                      //file.Seek(0, CFile::end);
                      file.SeekToEnd();
                      file.WriteString(logfile);
                      file.WriteString(_T("\n"));
                      file.Close();
                      }

                      [VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

                      modified on Thursday, September 4, 2008 6:46 AM

                      C Offline
                      C Offline
                      cpvc
                      wrote on last edited by
                      #13

                      ok when i am useing your code then i am geting error..Plz help me

                      error C2660: 'CStdioFile::Open' : function does not take 1 arguments
                      error C2660: 'CStdioFile::Seek' : function does not take 1 arguments
                      error C2065: 'logfile' : undeclared identifier1>
                      error C2660: 'CStdioFile::Open' : function does not take 1 arguments
                      error C2660: 'CStdioFile::Seek' : function does not take 1 arguments
                      error C2065: 'logfile' : undeclared identifier

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                      • C cpvc

                        ok when i am useing your code then i am geting error..Plz help me

                        error C2660: 'CStdioFile::Open' : function does not take 1 arguments
                        error C2660: 'CStdioFile::Seek' : function does not take 1 arguments
                        error C2065: 'logfile' : undeclared identifier1>
                        error C2660: 'CStdioFile::Open' : function does not take 1 arguments
                        error C2660: 'CStdioFile::Seek' : function does not take 1 arguments
                        error C2065: 'logfile' : undeclared identifier

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                        toxcct
                        wrote on last edited by
                        #14

                        god, I made a typo. you shouldn't have read

                        if (_T(file.Open("\\log.txt"), CFile::modeCreate | CFile::modeWrite | CFile::modeNoTruncate)) {

                        but this :

                        if (file.Open(_T("\\log.txt"), CFile::modeCreate | CFile::modeWrite | CFile::modeNoTruncate)) {

                        I fixed the previous post BTW. and sorry, I am at work, and I have no compiler, so I couldn't test it before posting...

                        [VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

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                        • T toxcct

                          god, I made a typo. you shouldn't have read

                          if (_T(file.Open("\\log.txt"), CFile::modeCreate | CFile::modeWrite | CFile::modeNoTruncate)) {

                          but this :

                          if (file.Open(_T("\\log.txt"), CFile::modeCreate | CFile::modeWrite | CFile::modeNoTruncate)) {

                          I fixed the previous post BTW. and sorry, I am at work, and I have no compiler, so I couldn't test it before posting...

                          [VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

                          C Offline
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                          cpvc
                          wrote on last edited by
                          #15

                          i was read but i think both have make same mistake..And mistake is

                          file.Seek(CFile::end)

                          this is not right and right one is this

                          file.Seek(0,CFile::end)

                          Any way thxs for help..

                          T 1 Reply Last reply
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                          • C cpvc

                            i was read but i think both have make same mistake..And mistake is

                            file.Seek(CFile::end)

                            this is not right and right one is this

                            file.Seek(0,CFile::end)

                            Any way thxs for help..

                            T Offline
                            T Offline
                            toxcct
                            wrote on last edited by
                            #16

                            cpvc++ wrote:

                            this is not right and right one is this file.Seek(0,CFile::end)

                            Yes you're right. BTW, you still can call CFile::SeekToEnd() which takes no parameters, and moves directly to the end of file. anyway, does it work now for you ?

                            [VisualCalc][Binary Guide][CommDialogs] | [Forums Guidelines]

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