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Depending on the condition of different Cast

Discussion in 'MFC' started by creative, May 28, 2010.

  1. creative

    creative New Member

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    Hi,

    I have a condition and the requirement should be, a condition variable to a different type to cast depending. Since I do not want to write anew every time
    Code:
    if (condition == 1) 
    Object1 var = (Object1) getVar (); 
    else if (condition == 2) 
    Object2 var = (Object2) getVar (), 
    etc. ..
    I wanted to ask if there any other possibility, one that saves me and I do not think straight. (The best one member variable to the appropriate type always corresponds.)
     
  2. techme

    techme New Member

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    How about this:
    Code:
    Var object1 = (Object1) getVar (); 
    Object2 var = (Object2) getVar ();
    Anaon you had yourself a little bit of concrete to express what you really want.
     
  3. meyup

    meyup New Member

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    I guess it's quite simply dadrum of an object whose true type is known casting automated to.

    as is a Enum Type (Bool, Integer, Float)
    should now be something like going

    Code:
    if (type == bool) bool var = static_cast < bool > (getVar ()) 
    if (Type == integer) integer var = static_cast < bool > (getVar ());
    ...
    I just think that the type derivations one different and the same base class .
     
  4. creative

    creative New Member

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    correct!

    also right! But for special functions of derived classes to come to the (or the derived class to create an object), I have to base object to cast it.

    So the question is only how to prevent I do every time I do have a query 20 different types start between the need to find out what type it is just an object and what type I need to create.
     
  5. pankaj.sea

    pankaj.sea New Member

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  6. techinspiration

    techinspiration New Member

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    Without C + + and the Rumgecaste of classes would pure C on Rumgecaste where actually executed code ie the functions themselves run out in, and should your requirements but meet it?
    as
    Code:
    enum (PLUS, MINUS, TIME) 
    
    void plus (int i, int j) printf ("% d \ n (", i + j);) 
    void minus (int i, int j) (printf ("% d \ n, ij);) 
    void times (int i, int j) printf ("% d \ n (", i * j);) 
    
    # define dispatch (x) ((x) == PLUS? plus: (x ) == MINUS? minus: times) 
    
    dispatch (PLUS) (2.5), 
    dispatch (MINUS) (1.99), 
    dispatch (MAL) (5.5);
    the parameter to dispatch you can so your terms dynamic design accordingly.

    With C + + is even without casts, if you dispatching method level ranges, you have everything in one class:

    Code:
    enum (PLUS, MINUS, TIME) 
    class D ( 
    int x; 
    void plus (int a, int b) (printf ("% d", a + b);) 
    void minus (int a, int b) (printf ( "% d", from);) 
    void times (int a, int b) (printf ("% d", a * b);) 
    public: 
    D (int p) (x = p;) 
    void doit (int a , int b) ( 
    switch (x) ( 
    case PLUS: plus (a, b) break; 
    case MINUS: minus (a, b) break; 
    case MAL: mal (a, b) break; 
    )));
    Code:
    D plus (PLUS), minus (MINUS), sometimes (MAL); 
    plus.doit (1.2); 
    minus.doit (3.4); 
    mal.doit (5.6);
    Again, your conditions you can give to the constructor.
     

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