与C / C++不同,C#中的结构可以具有方法,字段,索引器,运算符方法,属性或事件等成员。成员可以具有公共,私有和内部访问说明符。
指针是存储相同类型变量的地址的变量,即,int指针可以存储整数的地址,char指针可以存储char的地址,并且对于所有其他基本或用户定义的数据类型,其指针都类似。
您可以通过以下方式使用结构类型为指针的结构成员:
1)使用箭头运算符:如果结构的成员是公共的,则可以使用箭头运算符(->)直接访问它们。如果它们是私有的,则可以定义用于访问值的方法,并使用指针来访问方法。箭头运算符可用于访问结构变量以及方法。
句法:
PointerName->memberName;
例子:
// C# Program to show the use of
// pointers to access struct members
using System;
namespace GFG {
// Defining a struct Student
struct Student
{
// With members
// roll number and marks
public int rno;
public double marks;
// Constructor to initialize values
public Student(int r, double m)
{
rno = r;
marks = m;
}
}; // end of struct Student
class Program {
// Main Method
static void Main(string[] args)
{
// unsafe so as to use pointers
unsafe
{
// Declaring two Student Variables
Student S1 = new Student(1, 95.0);
Student S2 = new Student(2, 79.5);
// Declaring two Student pointers
// and initializing them with addresses
// of S1 and S2
Student* S1_ptr = &S1;
Student* S2_ptr = &S2;
// Displaying details of Student using pointers
// Using the arrow ( -> ) operator
Console.WriteLine("Details of Student 1");
Console.WriteLine("Roll Number: {0} Marks: {1}",
S1_ptr -> rno, S1_ptr -> marks);
Console.WriteLine("Details of Student 2");
Console.WriteLine("Roll Number: {0} Marks: {1}",
S2_ptr -> rno, S2_ptr -> marks);
} // end unsafe
} // end main
} // end class
}
输出:
2)使用解引用运算符:您还可以使用指针上的解引用运算符来访问结构元素,该运算符使用星号解引用指针,然后使用点运算符指定结构元素。
句法:
(*PointerName).MemberName;
例子:
// C# Program to illustrate the use
// of dereferencing operator
using System;
namespace GFG {
// Defining struct Employee
struct Employee{
// Elements Eid and Salary
// With properties get and set
public int Eid
{
get;
set;
}
public double Salary
{
get;
set;
}
}
; // Employee ends
class Program {
// Main Method
static void Main(string[] args)
{
// unsafe so as to use pointers
unsafe
{
// Declaring a variable of type Employee
Employee E1;
// Declaring pointer of type Employee
// initialized to point to E1
Employee* ptr = &E1;
// Accessing struct elements using
// dereferencing operator
// calls the set accessor
(*ptr).Eid = 1101;
(*ptr).Salary = 1000.00;
Console.WriteLine("Details of Employee");
// calls the get accessor
Console.WriteLine("Employee Id: {0}\nSalary: {1}",
(*ptr).Eid, (*ptr).Salary);
} // end unsafe
} // end Main
} // end class
}
输出:
注意:要在Visual Studio(2012)上编译不安全代码,请转到项目–> ProjectName属性–>生成–>选中“允许不安全代码”框。