Passing custom classes as arguments

This is a discussion on Passing custom classes as arguments within the C++ Programming forums, part of the General Programming Boards category; Code: class CEmployee { string name; ... }; CEmployee (const CEmployee &e ) { int i; this->name = e.name; ... ...

  1. #1
    Registered User
    Join Date
    Jul 2005
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    22

    Strings don't copy over

    Code:
    class CEmployee {
    string name; ...
    };
    
    CEmployee (const CEmployee &e ) {
    		int i;
    
    		this->name = e.name;
    ...
    	}
    
    ...
    
    void ProcessMorning(std::vector<CEmployee> &vEmps, int day) {
    	unsigned int i;
    	std::vector<CEmployee> openers;
    
    	for(i=0; i<vEmps.size(); i++) {
    		openers.push_back(vEmps[i]);
    	}
    }
    When I try pushing the copy of the copy of the CEmployee class into the vector, the name string doesn't copy over.
    Last edited by Sfpiano; 07-12-2005 at 10:27 PM.

  2. #2
    the hat of redundancy hat nvoigt's Avatar
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    Hannover, Germany
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    I'm not familiar with STL vectors, but you should overload operator = in addition to the copy constructor.

    PHP Code:
    #include <string>

    class CEmployee
    {
    private:
        
    std::string m_strName;

    public:
        
    CEmployee( const CEmployeeother 
        {
            *
    this other;
        }

        
    CEmployeeoperator = ( const CEmployeeother )
        {
            
    this->m_strName other.m_strName;

            return *
    this;
        }
    }; 
    hth
    -nv

    She was so Blonde, she spent 20 minutes looking at the orange juice can because it said "Concentrate."

    When in doubt, read the FAQ.
    Then ask a smart question.

  3. #3
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    Tried that didn't work. I really don't get it because it's just the string parameter that doesn't copy over, everything else does.

  4. #4
    Registered User
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    7,317
    There is nothing wrong with the posted code. The problem is elsewhere.

    If you have only strings and POD types (like int, bool or double) in your class, you don't need a copy constructor or copy assignment operator. It will work automatically.

  5. #5
    Registered User hk_mp5kpdw's Avatar
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    ...and if your openers vector is just supposed to be a copy of the vEmps vector, you should be able to forgo the for loop and just use the vector's own copy constructor.

    Code:
    void ProcessMorning(std::vector<CEmployee> &vEmps, int day) {
        std::vector<CEmployee> openers(vEmps);  // Do this instead of the 'for' loop
    
        ...
    
    }
    Also, technically if you wanted to use the for loop, your i variable should be of type vector<int>::size_type and not unsigned int.
    "Owners of dogs will have noticed that, if you provide them with food and water and shelter and affection, they will think you are god. Whereas owners of cats are compelled to realize that, if you provide them with food and water and shelter and affection, they draw the conclusion that they are gods."
    -Christopher Hitchens

  6. #6
    Tropical Coder Darryl's Avatar
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    I agree the problem is somewhere elsw amd I am going to take a guess that you are tying to use the vector openers outside of the ProcessMorning function which you can't because openers will be a local variable.

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