将XML文件保存在C＃中

Question

I have a program that will take in a name and a score, it will compare the score to a scoreboard located in a xml file, and then sort it fro highest to the lowest score. it works until i shutdown the program and restarts it, then it looks like it has not saved the changes to the xml file.

this is the xml file:

<?xml version="1.0" encoding="utf-8" ?>
<Highscore>
  <Data>
    <score number="1" value="250" name="per"/>
    <score number="2" value="200" name="ole"/>
    <score number="3" value="100" name="gunnar"/>
    <score number="4" value="50" name="lars"/>
    <score number="5" value="25" name="bob"/>
  </Data>
</Highscore>

and this is the code in the program:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

using System.Xml.Linq;


namespace XML
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();

            write();
        }

        private void btnExecute_Click(object sender, EventArgs e)
        {
            SaveHighscore(ChechForBetterScore(LoadHighscore()));

            write();
        }

        private List<highscore> LoadHighscore()
        {
            List<highscore> temp = new List<highscore>();

            var xmlDocument = XDocument.Load("Highscore.xml");

            for(int i = 1; i <= 5; i++)
            {
                var element = xmlDocument.Root
                                .Element("Data")
                                .Elements("score")
                                .FirstOrDefault(x => (string)x.Attribute("number") == (i.ToString()));

                highscore _temp = new highscore();

                _temp.name = element.Attribute("name").Value;
                _temp.score = Convert.ToInt32(element.Attribute("value").Value);

                temp.Add(_temp);
            }

            return temp;
        }

        private List<highscore> ChechForBetterScore(List<highscore> scoreBoard)
        {
            List<highscore> temp = new List<highscore>();

            try
            {
                int userScore = Convert.ToInt32(txtScore.Text);
                string userName = txtName.Text;

                int tempScoreA = userScore;
                int tempScoreB;

                string tempNameA = userName;
                string tempNameB;

                for(int i = 0; i < scoreBoard.Count; i++)
                {
                    highscore _temp = new highscore();

                    if(scoreBoard[i].score < userScore)
                    {
                        tempScoreB = scoreBoard[i].score;
                        tempNameB = scoreBoard[i].name;

                        _temp.score = tempScoreA;
                        _temp.name = tempNameA;

                        tempScoreA = tempScoreB;
                        tempNameA = tempNameB;

                        temp.Add(_temp);
                    }

                    else
                    {
                        _temp.name = scoreBoard[i].name;
                        _temp.score = scoreBoard[i].score;

                        temp.Add(_temp);
                    }
                }

            }
            catch(Exception trown)
            {
                MessageBox.Show(trown.Message, "Error");
            }

            return temp;
        }

        private void SaveHighscore(List<highscore> scoreboard)
        {
            var xmlDocument = XDocument.Load("Highscore.xml");

            for(int i = 1; i <= 5; i++)
            {
                var element = xmlDocument.Root
                                .Element("Data")
                                .Elements("score")
                                .FirstOrDefault(x => (string)x.Attribute("number") == (i.ToString()));

                element.Attribute("name").Value = scoreboard[i - 1].name;
                element.Attribute("value").Value = (scoreboard[i - 1].score).ToString();
            }

            xmlDocument.Save("Highscore.xml");
        }

        private void write()
        {
            labOutput.Text = "";

            List<highscore> temp = LoadHighscore();

            for(int i = 0; i < temp.Count; i++)
            {
                labOutput.Text += (i + 1).ToString() + ". " + temp[i].name + ": " + (temp[i].score).ToString() + "\n";
            }
        }

        struct highscore
        {
            public int score;
            public string name;
        }
    }
}

i can't find how you get it to save it after you shut down the program, just comment if there is something that you need more information on

Answer 1

I assume that Form1 will work as main window of your application. In such case you should bind callback method to application Exit event in App.xaml. From body of that callback method you may refer to your main window by using MainWindow property. You may cast it to Form1 type and invoke method that will save the results (make it public).