Oct 16, 2016 at 4:24pm
hello every one ;
I have a little problem
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// englconv.cpp
// conversions: Distance to meters, meters to Distance
#include <iostream>
using namespace std;
////////////////////////////////////////////////////////////////
class Distance //English Distance class
{
private:
const float MTF; //meters to feet
int feet;
float inches;
public: //constructor (no args)
Distance() : feet(0), inches(0.0), MTF(3.280833F)
{ } //constructor (one arg)
Distance(float meters) : MTF(3.280833F)
{ //convert meters to Distance
float fltfeet = MTF * meters; //convert to float feet
feet = int(fltfeet); //feet is integer part
inches = 12*(fltfeet-feet); //inches is what's left
} //constructor (two args)
Distance(int ft, float in) : feet(ft),
inches(in), MTF(3.280833F)
{ }
void getdist() //get length from user
{
cout << "\nEnter feet: "; cin >> feet;
cout << "Enter inches: "; cin >> inches;
}
void showdist() const //display distance
{ cout << feet << "\'-" << inches << '\"'; }
operator float() const //conversion operator
{ //converts Distance to meters
float fracfeet = inches/12; //convert the inches
fracfeet += static_cast<float>(feet); //add the feet
return fracfeet/MTF; //convert to meters
}
};
////////////////////////////////////////////////////////////////
int main()
{
float mtrs;
Distance dist1 = 2.35F; //uses 1-arg constructor to
//convert meters to Distance
cout << "\ndist1 = "; dist1.showdist();
mtrs = static_cast<float>(dist1); //uses conversion operator
//for Distance to meters
cout << "\ndist1 = " << mtrs << " meters\n";
Distance dist2(5, 10.25); //uses 2-arg constructor
mtrs = dist2; //also uses conversion op
cout << "\ndist2 = " << mtrs << " meters\n";
//dist2 = mtrs; //error, = won't convert
return 0;
}
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// strconv.cpp
// convert between ordinary strings and class String
#include <iostream>
using namespace std;
#include <string.h> //for strcpy(), etc.
////////////////////////////////////////////////////////////////
class String //user-defined string type
{
private:
enum { SZ = 80 }; //size of all String objects
char str[SZ]; //holds a C-string
public:
String() //no-arg constructor
{ str[0] = '\0'; }
String( char s[] ) //1-arg constructor
{ strcpy(str, s); } // convert C-string to String
void display() const //display the String
{ cout << str; }
operator char*() //conversion operator
{ return str; } //convert String to C-string
};
////////////////////////////////////////////////////////////////
int main()
{
String s1; //use no-arg constructor
//create and initialize C-string
char xstr[] = "Joyeux Noel! ";
s1 = xstr; //use 1-arg constructor
// to convert C-string to String
s1.display(); //display String
String s2 = "Bonne Annee!"; //uses 1-arg constructor
//to initialize String
cout << static_cast<char*>(s2); //use conversion operator
cout << endl; //to convert String to C-string
return 0; //before sending to << op
}
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line 56 in the first
the one argument constructor(for converting) isn't working but
in line 29 in the second
it is working properly why??
Last edited on Oct 16, 2016 at 4:29pm
Oct 16, 2016 at 8:57pm
this is a small question!
