// mystring.cpp // // Programmer: Carmen Sarro // Copyright (c) Microsoft Corporation, 1997 // // Microsoft Technical Education // C++ Programming // Lab 1 #include "pch.h" #pragma hdrstop MyString::MyString() { Zero(); *data = L'\0'; m_len = 0; } MyString::MyString(wchar_t *str) { Zero(); m_len = wcslen(str); // Since strlen returns the number of characters in str, excluding the terminal NULL, // and since strncpy does not automatically append the terminal NULL, // if m_len < MAX_LEN we want to copy m_len + 1 characters because we assume the // last character of the source string is the terminal NULL. Otherwise we explicitly // set the last element to the terminal NULL. if (m_len >= MAX_LEN - 1){ m_len = MAX_LEN - 1; wcsncpy(data, str, m_len); data[m_len] = L'\0'; } else { wcscpy(data, str); } } MyString::MyString (const MyString& MyStr) { wcscpy(data, MyStr.data); m_len = wcslen(MyStr.data); this->NullTerminate(); } const MyString& MyString::operator= (PCWSTR lp) { Zero(); wcscpy(data, lp); m_len = wcslen(lp); this->NullTerminate(); return (*this); } const MyString& MyString::operator= (const MyString& MyStr) { wcscpy(data, MyStr.data); m_len = MyStr.m_len; this->NullTerminate(); return (*this); } const wchar_t* MyString::wcharptr() { return data; } int MyString::len() { return m_len; } void MyString::append(MyString str) { wcsncat(data, str.data, MAX_LEN - m_len - 1); m_len += wcslen(data + m_len); this->NullTerminate(); } BOOLEAN MyString::append(const wchar_t *str) { BOOLEAN fDidCopy = FALSE; UINT Length = 0; if (str == NULL || (wcslen(str) + m_len > MAX_LEN + 1) ) { return fDidCopy; } wcsncat(data, str, MAX_LEN - m_len - 1); m_len += wcslen(data); fDidCopy = TRUE; this->NullTerminate(); return fDidCopy; } int compare(MyString firstStr, MyString secondStr) { return wcscmp(firstStr.wcharptr(), secondStr.wcharptr()); } const wchar_t* MyString::c_str() const { return (data); } void MyString::Zero() { UINT i = 0; m_len = 0; for (i = 0; i < MAX_LEN; i++) { data[i] = 0; } } VOID MyString::NullTerminate() { if (data[m_len] != L'\0') { data[++m_len] = L'\0'; } }