8-2.cs

java基础方面的一些实例代码

//程序8-2
using System;
namespace School
{
	public class Student 
	{
		private string studName;
		private int studID;
		private string Department;
		public Student(){}
		public Student(string str, int id, string dept)
		{
			studName=str;
			studID=id;
			Department=dept;
		}
		public void FindInfo(int id)
		{
			if(id==studID)
			  Console.WriteLine("{0}is a student in the {1} Department ", studName,Department);
		}
		
		//params参数实际上是不定长一维数组或交错数组，只能作为参数列表的最后一个参数。
		//定义形参使用params关键字，调用时不用该关键字
		//购书费用计算
		public double BooksTotleFee (params double [] bookFee)
		{
			float totle=0f;
			foreach(float fee in bookFee) totle+=fee;
			return totle;
		}
		//out参数与ref类似，直接将引用传递给方法，不在存储器中为参数开设新的空间。
		//不同之处是：调用前不需要对参数作初始化，在方法结束前必须对out参数赋值。
		// ave: 平均成绩；specave：加权平均成绩；score[0][]={"课程名","学分","成绩"};....
		public void SpecAverage(out double ave,out double specave,params string [][] score)
		{
			double creditsum=0.0,scoresum=0.0,specscoresum=0.0; 
			int n=0;
			foreach(string [] tt in score)
			{
				Console.Write("课程名: {0},学分: {1}, 成绩: {2}\n",tt[0],tt[1],tt[2]);
				n++; 
				creditsum+=Convert.ToDouble(tt[1]); //学分累计
				scoresum+=Convert.ToDouble(tt[2]);  //成绩累计
				specscoresum+=Convert.ToDouble(tt[1])*Convert.ToDouble(tt[2]); //加权成绩＝学分×成绩
			}
			ave=scoresum/n;                 //在方法结束前必须对out参数赋值
			specave=specscoresum/creditsum; //在方法结束前必须对out参数赋值
		}			
	}
	public class Test
	{
		public static void Main()
		{
			double Ave,SpecAve;
			Student AStudent=new Student("张三", 0518288,"计算机");
			Student AnotherStudent = new Student("李四",0518277,"计算机");
			AStudent.FindInfo(0518288);
			//调用前不需对Ave和SpecAve赋值，这是与ref不同点。
			AStudent.SpecAverage(out Ave,out SpecAve,new string [3][]{new string []{"JAVA程序设计","4","87"},new string[] {".NET应用开发","6","79"},new string[] {"Web开发技术","4","89"}});
			Console.WriteLine("平均成绩：{0}  加权平均成绩：  {1}", Ave,SpecAve);
			Console.WriteLine("书费："+ AStudent.BooksTotleFee(36.5, 41.5, 38));
			AnotherStudent.FindInfo(0518277);
			string [][] sss=new string [2][]{new string[]{"体育","2","100"},new string[]{"法律与道德","4","60"}};
			AnotherStudent.SpecAverage(out Ave, out SpecAve,sss);
			Console.WriteLine("平均成绩：{0}  加权平均成绩：  {1}", Ave,SpecAve);
			Console.WriteLine("书费："+ AnotherStudent.BooksTotleFee(30.5, 11, 28));
		}
	}
}