Thread: Press Enter Twice

  1. #1
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    Question Press Enter Twice

    Hi, I`m new here and, of course, have a small problem.
    I need to create a program with VC++ 6 Builder where:
    Press ENTER once - open picture,
    Press ENTER Twice - start a music.

    I can`t figure out how to check if user press ENTER twice, can anybody help me?

    My Code:
    Code:
    void __fastcall TForm1::ListBox1KeyPress(TObject *Sender, char &Key)
    {
    switch( Key )
      {
       case  'VK_RETURN':
       { atidarytpav(); }
       break;
    }

  2. #2
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    You could do something as simple as using a control_int, whereas if int_control==1, do this, else (if int_control==2) do something else, then reset int_control back to '0'. It's a simple hack -

  3. #3
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    Can you explaining more or could you give me a very tiny example?

  4. #4
    and the Hat of Guessing tabstop's Avatar
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    How fast do you need to press the enter key? If speed isn't an issue, then you can just, in your VK_RETURN case, count how many times you've been there -- the first time show the picture, the second time play the music, etc.

  5. #5
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    Ok I have this script
    Code:
    int pressCount = 0;
    void __fastcall TForm1::ListBox1KeyPress(TObject *Sender, char &Key)
    {
       
    switch( Key )
      {
       case  'VK_RETURN':
       { 
          atidarytpav(); 
          pressCount = ++pressCount % 2 }
          if (count != 0)
          {
             //first time
          }
          else
          {
             //second time
             pressCount = 0;
          }
    
       break;
    }
    but now say

    Code:
    Undefined symbol 'count'
    Do I need some library or what .. ?

  6. #6
    and the Hat of Guessing tabstop's Avatar
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    You call it pressCount everywhere else, why not that line too?

  7. #7
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    it wont work when i call him there

  8. #8
    and the Hat of Guessing tabstop's Avatar
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    Quote Originally Posted by Alone882 View Post
    it wont work when i call him there
    Of course it will.

  9. #9
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    Code:
     if(pressCount!=0){
    
     // do something
    
     }
    How is that going to allow you to ever reach your else statement? pressCount is always going to != 0. You're using odd/even comparative here? I imagine you could, but then there'd be no reason to reset pressCount back to '0'

    more like;

    Code:
     ++pressCount;
    
     if(pressCount<2)
      {
     //do something
      }
    
       else {
    
        //do something else
    
       presCount=0;
     }

  10. #10
    and the Hat of Guessing tabstop's Avatar
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    Quote Originally Posted by Oldman47 View Post
    Code:
     if(pressCount!=0){
    
     // do something
    
     }
    How is that going to allow you to ever reach your else statement? pressCount is always going to != 0. You're using odd/even comparative here? I imagine you could, but then there'd be no reason to reset pressCount back to '0'

    more like;

    Code:
     ++pressCount;
    
     if(pressCount<2)
      {
     //do something
      }
    
       else {
    
        //do something else
    
       presCount=0;
     }
    If pressCount is 1, then ++pressCount % 2 would be 0. I suppose there might be some sequence point issues going on.

  11. #11
    and the hat of int overfl Salem's Avatar
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    More waste of effort guys -> Press Enter Twice - C++
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.

  12. #12
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    Sry Guys, but this code wont work I try
    Code:
    switch( Key )
      {
       case  'VK_RETURN':
       { 
          pressCount = ++pressCount % 2 }
          if (pressCount != 0)
          {
             //first time
          }
          else
          {
             //second time
             pressCount = 0;
          }
    
       break;
    And
    Code:
    int pressCount = 0;
    switch( Key )
      {
       case 'VK_RETURN:
       {
          if (pressCount == 0)
          {
             //first time
             ++pressCount;
          }
          else
          {
             //second time
             pressCount = 0;
          }
        }
       break;
    No one will work

  13. #13
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    Pls somebody help :/

  14. #14
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    Finally I figure out how to solve this problem, thank you

  15. #15
    C++まいる!Cをこわせ!
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    This looks like some type of Borland stuff. Firstly, I'd stay away from Borland stuff. It's old. It's oudated.
    Secondly, this forum is more about pure C++ and not what you're asking. You are asking questions about some sort of graphical framework, which does not belong in this forum.
    Quote Originally Posted by Adak View Post
    io.h certainly IS included in some modern compilers. It is no longer part of the standard for C, but it is nevertheless, included in the very latest Pelles C versions.
    Quote Originally Posted by Salem View Post
    You mean it's included as a crutch to help ancient programmers limp along without them having to relearn too much.

    Outside of your DOS world, your header file is meaningless.

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