C#将一个列表的值除以另一个列表的值以生成新列表

时间:2015-02-06 18:43:18

标签: c# list listbox division

我希望划分每个列表的相应值,以便生成一个新列表,其中包含我的两个列表中每个相应索引的划分结果。我的两个列表都是8个值,并且都是int列表。我目前正在创建两个像这样划分的列表:

private void StartSchedule_Click(object sender, EventArgs e)
    {
        string ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=F:\A2 Computing\C# Programming Project\TriHard.accdb";
        string SelectQuery = "SELECT Time.AthleteID, Athlete.AthleteName, Time.EventTime, Event.EventDistance FROM Event INNER JOIN (Athlete INNER JOIN [Time] ON Athlete.[AthleteID] = Time.[AthleteID]) ON Event.[EventID] = Time.[EventID];";
        OleDbConnection Connection = new OleDbConnection(ConnectionString);
        OleDbCommand Command = new OleDbCommand(SelectQuery, Connection);
        Command.Connection.Open();

        OleDbDataReader Reader = Command.ExecuteReader(CommandBehavior.CloseConnection);

        PaceCalculator pace = new PaceCalculator();

        List<int> Distancelist = new List<int>();
        List<int> Secondslist = new List<int>();
        List<int> Pacelist = new List<int>();
        while (Reader.Read())
        {
            pace = new PaceCalculator();
            pace.Distance = (int)Reader["EventDistance"];
            int DistanceInt = Convert.ToInt32(pace.Distance);
            Distancelist.Add(DistanceInt);

            pace = new PaceCalculator();
            pace.Time = (string)Reader["EventTime"]; //Reads in EventTime
            double Seconds = TimeSpan.Parse(pace.Time).TotalSeconds; //Converts the string into HH:MM:SS as a double
            int SecondsInt = Convert.ToInt32(Seconds); //Converts the double into an integer, returning the seconds in the total time
            Secondslist.Add(SecondsInt); //Adds the Seconds for each time to the list;

            //Need to fix this currently returns just 0
            var Pacelist2 = PaceCalc(Distancelist, Secondslist);
            listBox3.DisplayMember = "PaceInt";
            listBox3.DataSource = (Pacelist2);



        }


        listBox1.DisplayMember = "DistanceInt";
        listBox1.DataSource = Distancelist;

        listBox2.DisplayMember = "SecondsInt";
        listBox2.DataSource = Secondslist;

这是我正在调用的函数,它试图划分列表,但似乎没有工作:

public List<int> PaceCalc(List<int> Dlist, List<int> Slist)
    {
        PaceCalculator pace = new PaceCalculator();
        List<int> Plist = new List<int>();

        pace = new PaceCalculator();
        for (int i = 0; i == Dlist.Count; i++)
        {
            int PaceInt = Dlist[i] / Slist[i];
            Plist.Add(PaceInt);
        }
        return Plist;
    }

我希望在listBox3中显示除法的结果。我是否正确划分列表,如何在列表框中显示?

2 个答案:

答案 0 :(得分:9)

您的for循环永远不会执行,因为您正在测试i == Dlist.Count。它应该是:

for (int i = 0;i < Dlist.Count; i++)

或者,您可以使用LINQ执行此操作:

public List<int> PaceCalc(List<int> Dlist, List<int> Slist)
{
    return Dlist.Zip(Slist, (a, b) => a / b).ToList();
}

答案 1 :(得分:3)

几个问题:

首先,您需要将for循环中的检查修改为i < Dlist.Count。您当前的支票i == Dlist.Count是错误的。

所以你的方法是:

public List<int> PaceCalc(List<int> Dlist, List<int> Slist)
{
    List<int> Plist = new List<int>();
    for (int i = 0; i < Dlist.Count; i++)
    {
        int PaceInt = Dlist[i] / Slist[i];
        Plist.Add(PaceInt);
    }
    return Plist;
}

(我已移除PaceCalculator pace = new PaceCalculator();,因为您的方法根本不需要它)

二。您不必为DisplayMember

指定ListBox3
var Pacelist2 = PaceCalc(Distancelist, Secondslist);
listBox3.DataSource = Pacelist2;

虽然,第二个问题不会导致任何错误/异常,因为找不到DisplayMember,它将使用默认的ToString重载,您将获得数字