The Assignment Functions. McGraw-Hill The Complete Reference Fourth Edition

C h a p t e r 3 9 : I n t e g r a t i n g N e w C l a s s e s : A C u s t o m S t r i n g C l a s s

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The Assignment Functions

You can assign a StrType object a string in two ways. First, you can assign another StrType object to it. Second, you can assign it a quoted string. The two overloaded operator=( ) functions that accomplish these operations are shown here:

// Assign a StrType object to a StrType object.

StrType StrType::operator=(StrType &o)

{

StrType temp(o.p); if(o.size > size) { delete [] p; // free old memory try { p = new char[o.size];

} catch (bad_alloc xa) { cout << "Allocation error\n"; exit(1);

} size = o.size;

} strcpy(p, o.p); strcpy(temp.p, o.p);

} return temp;

// Assign a quoted string to a StrType object.

StrType StrType::operator=(char *s)

{ int len = strlen(s) + 1; if(size < len) { delete [] p; try { p = new char[len];

} catch (bad_alloc xa) { cout << "Allocation error\n"; exit(1);