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→IO_Label
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===IO_Label===
'''IO_Label''' class mostly, encapsulates the '''[[OOP344_Assignment_One#void_io_display.28const_char_.2Astr.2C_int_row.2C_int_col.2C_int_len.29|io_display()]]''' function.
Inherit a new class called IO_Label from IO_Field to Display a text message on IO_Form. In addition to the attributes of its parent IO_Field, IO_Label has a private integer attribute called _len. _len is used to hold the length of Field in which the text is to be displayed.
IO_Label could hold holds its data dynamically or simply and will never point to an external one. Because of this IO_Label also has a boolean attribute called _dynamic that will hold the type of data within; being dynamic memory (value true), or external memory (value false)
'''IO_Label''' can be created in two ways;
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IO_Label(int row, int col, int len);
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This constructor will create an empty (blank) IO_Label with capacity of len characters.
In this case '''row''' and '''col''' are passed to the parent for initialisation and '''_len''' (the attribute) is set to the incoming argument '''len'''.
''Note that '''data''' is a void pointer; to use it here, you must cast it to a character pointer!''<br />
IO_Label(char* str, int row, int col, int len = -1);
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====Public Methods====
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void Display(void);
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void Set(const void* str);
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'''Set()''' will copy the content of '''str''' into '''IO_Field::_data''' up to '''_len''' characters, if '''_len''' is not negative.
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bool IO_Label::Editable(void)const;
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'''Editable()''' returns false!.
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int Edit(IO_Form* Owner=(IO_Form*)0);
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~IO_Label(void);
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The destructor, delete[]s the '''_data''' only if . (make sure '''_dynamic_data''' is truecasted to char* before deleting.
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IO_Label &operator=(const char* str);
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