Predict the output of following C++ program: 1 #include <iostream> 2 using namespace std; 3 4 class A 5 { 6 public: 7 A() { cout << "A's Constructor Called " << endl; } 8 }; 9 10 class B 11 { 12 static A a; 13 public: 14 B() {…

Static Classes and Static Class Members A static class is basically the same as a non-static class, but there is one difference: a static class cannot be instantiated. In other words, you cannot use the new keyword to create a variable of the class t…

You can link data that doesn't change very often to SQL Source Control. This lets you commit data changes to source control. To source-control data: 1.In the Object Explorer, right-click the database or table with data you want to source control and…

advantage of properties: 1 properties can be used in data binding, public data member can not. 2 data validation can be wrote inside setter method. easy to implement, also multithread feature. 3 the access level of getter and setter method can be res…

tomcat service.xml <Context docBase="/path/to/images" path="/images" /> resin resin.conf  <host id="" root-directory=".">      <web-app id="/" root-directory="D:/resin-pro-3.1.10/webapp…

将成员变量隐藏在函数接口的背后,可以为“所有可能的实现”提供弹性, 假设我们有一个public成员变量,而我们最终取消了它,多少代码可能会被破坏呢?那是一个不可知的大量. protected成员变量就像public成员一样缺乏封装性(所有使用它的derived都会被破坏)…

NOTE: 1.切记将成员变量声明为private.这可赋予客户访问数据的一致性 可细微划分访问控制 允诺约束条件获得保证,并提供class作者以充分的实现弹性. 2.protected 并不比public更具有封装性.…

In C++, class variables are initialized in the same order as they appear in the class declaration. Consider the below code. 1 #include<iostream> 2 3 using namespace std; 4 5 class Test 6 { 7 private: 8 int y; 9 int x; 10 public: 11 Test() : x(10), y…

extraction from The C++ Programming Language, 4th. edition, Bjarne Stroustrup If no initializer is specified, a global, namespace, local static, or static member (collectively called static objects) is initialized to {} of the appropriate type. We cl…

一.Data Member 的绑定(The binding of Data Member) extern float x; class Point3d { public: Point3d( float, float, float); float X() const { return x; } void X( float new_x ) const { x = new_x; } // ... private: float x,y,z; }; 请问 Point3d::X()传回哪一个x?是class…