template相關
阿新 • • 發佈:2017-05-28
closed std include class val aps 參數 let display
template模板是c++中支持多態的工具,使用模板可以使用戶為類或函數聲明一種一般的模式,使得該模板試用於任意類型的參數。
函數模板:
定義如下:
template <typename T> void swap(T& a , T& b){ T temp; temp = a; a = b; b = temp; }View Code
使用如下:
#include<stdio.h> int main(){ int num1 = 0, num2 = 1; swap<int>(num1 , num2); printf(View Code"num1=%d,num2=%d\n",num1,num2); return 0; }
類模版:
定義如下:
template<class T> class Stack{ public: Stack(); ~Stack(); void push(T t); T pop(); bool isEmpty(); private: int m_maxSize ; int m_size ; T *m_pT ; } template <class T> Stack<T>::Stack(){ m_maxSizeView Code= 100; m_size = 0; m_pT = new T[m_maxSize]; } template <class T> Stack<T>::~Stack() { delete [] m_pT ; } template <class T> void Stack<T>::push(T t) { m_size++; m_pT[m_size - 1] = t; } template <class T> T Stack<T>::pop() { T t= m_pT[m_size - 1]; m_size--; return t; } template <class T> bool Stack<T>::isEmpty() { return m_size == 0; }
類模版使用:
#inlcude<stdio.h> int main(){ Stack<int> intStack; intStack.push(1); intStack.push(2); intStack.push(3); while (!intStack.isEmpty()) { printf("num:%d\n", intStack.pop()); } return 0; }View Code
模版參數:
模板除了有類型參數,也可以有普通的參數,也可以有默認的模板參數,例如:
template<class T, T def_val> class Stack{...}
如果想要對類模版的對象數量進行限制,可是使用int參數來配置這個累的最大對象數,如下:
template <class T,int maxsize = 100> class Stack { public: Stack(); ~Stack(); void push(T t); T pop(); bool isEmpty(); private: T *m_pT; int m_maxSize; int m_size; }; template <class T,int maxsize> Stack<T, maxsize>::Stack(){ m_maxSize = maxsize; m_size = 0; m_pT = new T[m_maxSize]; } template <class T,int maxsize> Stack<T, maxsize>::~Stack() { delete [] m_pT ; } template <class T,int maxsize> void Stack<T, maxsize>::push(T t) { m_size++; m_pT[m_size - 1] = t; } template <class T,int maxsize> T Stack<T, maxsize>::pop() { T t = m_pT[m_size - 1]; m_size--; return t; } template <class T,int maxsize> bool Stack<T, maxsize>::isEmpty() { return m_size == 0; }View Code
使用如下:
#include <stdio.h> int main() { int maxsize = 1024; Stack<int,1024> intStack; for (int i = 0; i < maxsize; i++) { intStack.push(i); } while (!intStack.isEmpty()) { printf("num:%d\n", intStack.pop()); } return 0; }View Code
template相關