c#方法调用导致的错误
本文关键字：错误 方法 调用 | 更新日期: 2023-09-27 18:21:04
我正在尝试修复这个错误，这样我就可以用我在内部声明的列表"school"中的4个实例来启动我的程序。然后我想允许用户按照自己的意愿操作列表。在我添加"Myfour"方法之前，一切都正常。如何调用此函数以避免出现堆栈溢出错误？我是编程和C#的新手，今天需要完成这项工作。
主要：
using System;
namespace Lab4
{
class MainClass
{
public static void Main (string[] args)
{
Console.WriteLine ("Welcome to the Course Monitoring System v1.0");
Course myCourse = new Course();
myCourse.Myfour ();
myCourse.Print ();
Course.Menu();
myCourse.Print ();
myCourse.Choice();
}
}
}
课程类别：
using System;
using System.Collections.Generic;
namespace Lab4
{
public class Course
{
private string courseNumber;
private string courseName;
private int courseHours;
public List<Course> school = new List<Course> ();
private int howmany=0;
private int totalcourse=0;
//This section is for returning and adjusting values of private data through the main program.
public string cn{
get {return courseNumber; }
set {if (value != null)
cn = value;
}
}
public string name{
get{ return courseName; }
set{if (value!="")
name=courseName;
}
}
public int hours{
get {return courseHours; }
set {if (value != 0)
hours = value;
}
}
public Course()
{
}
public Course (string name, string cn, int hours)
{
courseNumber = cn;
courseName = name;
courseHours = hours;
}
//This portion of code overrides the string and allows it to output the information held within the constructor.
public override string ToString ()
{
return courseNumber+" " + courseName + " " +" It is a " + courseHours + " hour course.";
}
//The menu application for my program
public static void Menu()
{
Console.WriteLine ("Please choose from one of the following options: ");
Console.WriteLine ("......................................................................");
Console.WriteLine ("1.)Start a new Course List.");
Console.WriteLine ("2.)Delete Course from Current List.");
Console.WriteLine ("3.)Print Current Course List.");
Console.WriteLine ("4.)Add Course to Current List.");
Console.WriteLine ("5.)Shutdown Program");
}
//This is the controller for the menu. It allows for functionality to control the tasks requested by the user.
public void Choice()
{
int selection=int.Parse(Console.ReadLine());
while (selection >5 || selection < 1) {
Console.WriteLine ("Choice invalid. Please choose between 1 and 5.");
selection = int.Parse (Console.ReadLine ());
}
if (selection == 4) {
Add ();
Menu ();
Choice ();
Console.WriteLine ();
}
if (selection == 2) {
Delete ();
Menu ();
Choice ();
Console.WriteLine ();
}
if (selection == 3) {
Print ();
Menu ();
Choice ();
Console.WriteLine ();
}
if (selection == 1) {
New ();
Menu ();
Choice ();
Console.WriteLine ();
}
if (selection == 5) {
Console.WriteLine ();
Console.WriteLine ("Thank you for using this program for your scheduling needs.");
}
}
//This method when called will print a numbered list of courses refrenced by the created List
public void Print()
{
Console.WriteLine ();
Console.WriteLine ("Course Name.........Course Number.........Course Description........Course Hours");
Console.WriteLine ("********************************************************************************");
for (int i = 0; i < totalcourse; i++) {
int place = i + 1;
Console.WriteLine (place+".)"+school [i]);
}
Console.WriteLine ();
}
//This method will add an item to the end of the current list.
public void Add()
{
Console.WriteLine ();
Console.Write ("How many courses would you like to add at the end of your index?");
int numberAdded = int.Parse(Console.ReadLine ());
for (int i = 0; i < numberAdded; i++) {
Console.WriteLine ("Please use the following templet for your entries...");
Console.WriteLine ("Course Prefix, Course Name, Course Number, Course Hours, Course Description ");
school.Add (new Course (courseName = Console.ReadLine (), courseNumber = Console.ReadLine (), courseHours = int.Parse (Console.ReadLine ())));
}
totalcourse = totalcourse + numberAdded;
Console.WriteLine ();
}
//This method will delete an Item from the list based on the position 0-x based on x-1, the output that is seen by the user. After each iteration it will
//also create a list so that further deletions can be managed approiatly.
public void Delete()
{
if (totalcourse < 1) {
Console.WriteLine ();
Console.WriteLine ("There is nothing to delete!");
Console.WriteLine ();
}else{
Console.WriteLine ();
Console.Write ("How many entries do you wish to remove?");
int removed = int.Parse (Console.ReadLine ());
for (int i = 0; i < removed; i++) {
Console.WriteLine ("Please type the index line number of the item you wish to remove.");
int delete = int.Parse (Console.ReadLine ());
school.RemoveAt (delete - 1);
totalcourse = totalcourse - 1;
Print ();
}
}
Console.WriteLine ();
}
//This method is called to create a new list of Courses to be created by the user.
public void New()
{
Console.WriteLine ();
if (howmany > 0) {
Clear ();
} else {
Console.Write ("How many courses do you want to create? ");
howmany = int.Parse (Console.ReadLine ());
Console.WriteLine ();
for (int i = 0; i < howmany; i++) {
Console.WriteLine ();
Console.WriteLine ("Please use the following templet for your entries...");
Console.WriteLine ("Course Prefix, Course Name, Course Number, Course Hours, Course Description ");
school.Add (new Course (courseName = Console.ReadLine (), courseNumber = Console.ReadLine (), courseHours = int.Parse (Console.ReadLine ())));
}
totalcourse = totalcourse + howmany;
Console.WriteLine ();
}
}
//If there is already a list in place this method will be called and you will be asked if you wish to delete and start new.
public void Clear()
{
Console.WriteLine ();
Console.Write ("You want to discard old work and start a new list? Enter True or False...:");
bool clean=bool.Parse(Console.ReadLine());
if (clean == true) {
school.Clear ();
totalcourse = 0;
howmany = 0;
New ();
} else
Console.WriteLine ("No changes will be made. Exiting to Main Menu...");
Console.WriteLine ();
}
//This is the method to call the 4 predefined Courses
//----->This is the part of my code that is causing the stack overflow error that I cant figure out...
public void Myfour ()
{
Console.WriteLine ("These are four pre loaded courses.");
Course c1=new Course(name="Programming",cn="1101",hours=3);
Course c2=new Course(name="Algebra",cn="1101",hours=4);
Course c3=new Course(name="Chemistry 1",cn="1101",hours=4);
Course c4=new Course(name="Chemistry 1 Lab",cn="1101",hours=3);
school.Add (c1);
school.Add (c2);
school.Add (c3);
school.Add (c4);
}
}
}
堆栈溢出是由递归分配属性引起的。你不应该这样写：
public string cn{
get {return courseNumber; }
set {if (value != null)
cn = value;
}
}
看到cn又被分配了吗？您应该使用如下私有变量更改该行：
public string cn{
get {return courseNumber; }
set {if (value != null)
courseNumber = value;
}
}
对其他属性执行相同操作。还要注意课程名称中的错误。您应该使用value而不是courseName。这就是它应该有的样子。
public string cn{
get {return courseNumber; }
set {if (value != null)
courseNumber = value;
}
}
public string name{
get { return courseName; }
set
{
if (value != "")
courseName = value;
}
}
public int hours{
get {return courseHours; }
set {if (value != 0)
courseHours = value;
}
}
您有自己设置的属性：
public string cn
{
get { return courseNumber; }
set
{
if (value != null)
cn = value;
}
}
这将无限循环。你应该有一些私人字段来分配：
private string _cn;
public string cn
{
get { return _cn; }
set
{
if (value != null)
_cn = value;
}
}