C++类与结构体的初始化

c++类与结构体初始化 利用构造函数的重载 进行 默认参数初始化 部分参数初始化 全部参数初始化

使用初始化列表来初始化字段:

Node() :data(-1) , str("Blank") ,x(S) {
          
   
		cout << this->data << " " << this->str << " " << this->x << endl;
}

上面的语法等同于如下语法：

Node() :{
          
   
        this->data = -1;
		this->str = "Blank";
		this->x = S;
		cout << this->data << " " << this->str << " " << this->x << endl;
}

类的初始化：

```cpp
#include <iostream>
#include <string>
using namespace std;
class Node {
          
   

private:
	int data;
	string str;
	char x;

public :
	void init(int data, string str, char c) {
          
   
		this->data = data;
		this->str = str;
		this->x = c;
		cout << this->data << " " << this->str << " " << this->x << endl;
	}

	Node() :data(-1) , str("Blank"),x(S){
          
   
		cout << this->data << " " << this->str << " " << this->x << endl;
	}

	Node(string a) :data() , str(a), x(){
          
   
		cout << this->data << " " << this->str << " " << this->x << endl;
	}

	Node(int a, string b, char c) :data(a) , str(b), x(c) {
          
   
		cout << this->data << " " << this->str << " " << this->x << endl;
	}
};

int main() {
          
   
	
	Node Node1;
	Node Node2("Levi");
	Node Node3(1, "Hello", A);
}

结果：

结构体的初始化：

#include <iostream>
#include <string>
using namespace std;

struct Node {
          
   
	int data;
	string str;
	char x;

	void init(int data, string str, char c) {
          
   
		this->data = data;
		this->str = str;
		this->x = c;
		cout << this->data << " " << this->str << " " << this->x << endl;
	}

	Node() :data(-1) , str("Blank"),x(S){
          
   
		cout << this->data << " " << this->str << " " << this->x << endl;
	}

	Node(string a) :data() , str(a), x(){
          
   
		cout << this->data << " " << this->str << " " << this->x << endl;
	}

	Node(int a, string b, char c) :data(a) , str(b), x(c){
          
   
		cout << this->data << " " << this->str << " " << this->x << endl;
	}
};

int main() {
          
   
	
	Node Node1;
	Node Node2("Levi");
	Node Node3(1, "Hello", A);

}

结果：

C++中的类与结构体主要区别之一为 class中默认的是private，而struct中则是public