Question

我有一个使用以下类

创建的错误列表MyBugList

internal class BugDetails
{
    public int Id { get; set; }
    public string State { get; set; }
    public string Severity { get; set; }
}

我想根据State和Severity对这些错误进行分组。我使用以下代码来实现它。

var BugListGroup = (from bug in MyBugList
                             group bug by new
                             {
                                 bug.State,
                                 bug.Severity
                             } into grp
                             select new
                             {
                                 BugState = grp.Key.State,
                                 BugSeverity = grp.Key.Severity,
                                 BugCount = grp.Count()
                             }).OrderBy(x=> x.BugState).ToList();

这个linq查询给我输出如下

Closed      Critical    40
Active      Critical    167
Closed      Medium      819
Closed      Low         323
Resolved    Medium      61
Resolved    Low         11
Closed      High        132
Active      Low         17
Active      Medium      88
Active      High        38
Resolved    High        4
Resolved    Critical    22
Deferred    High        11

但是我希望得到如下的输出

            Critical    High    Medium  Total
Closed      3           4       5       12
Active      5           4       5       14
Resolved    6           4       5       15
Deferred    1           4       5       10
Total       15          16      20      51

是否可以通过MyBugList或BugListGroup

上的LINQ查询获取此信息

我想把输出作为一个列表，这样我就可以做到   提供数据网格。

注意：State和Severity值是动态的，不能进行硬编码

以下是Dmitriy Zapevalov提供的答案

的实施方法

private void button1_Click(object sender, EventArgs e)
{
    var grouped = MyBugList.GroupBy(b => b.State).Select(stateGrp => stateGrp.GroupBy(b => b.Severity));

    //Setting DataGrid properties
    dataGridBug.Rows.Clear();
    dataGridBug.Columns.Clear();
    dataGridBug.DefaultCellStyle.NullValue = "0";
    dataGridBug.DefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleCenter;

    //Declaring DataGrid Styles
    var gridBackColor = Color.AliceBlue;
    var gridFontStyle = new Font(Font, FontStyle.Bold | FontStyle.Italic);

    //Declaring column and row Ids
    const string stateColumnId = "State";
    const string totalColumnId = "Total";
    const string totalRowId = "Total";

    //Adding first column
    dataGridBug.Columns.Add(stateColumnId, stateColumnId);
    dataGridBug.Columns[0].DefaultCellStyle.Alignment = DataGridViewContentAlignment.MiddleLeft;

    //Adding other columns
    foreach (var strSeverity in MyBugList.Select(b => b.Severity).Distinct())
    {
        dataGridBug.Columns.Add(strSeverity, strSeverity);
    }

    //Adding Total Column
    var totColPos = dataGridBug.Columns.Add(totalColumnId, totalColumnId);
    var totCol = dataGridBug.Columns[totColPos];

    //Adding data to grid
    foreach (var state in grouped)
    {
        var nRow = dataGridBug.Rows.Add();
        var severities = state as IList<IGrouping<string, BugDetails>> ?? state.ToList();
        dataGridBug.Rows[nRow].Cells[0].Value = severities.First().First().State;
        var sevCount = 0;
        foreach (var severity in severities)
        {
            dataGridBug.Rows[nRow].Cells[severity.Key].Value = severity.Count();
            sevCount += severity.Count();
        }
        dataGridBug.Rows[nRow].Cells[totalColumnId].Value = sevCount;
    }


    //Adding total row
    var totRowPos = dataGridBug.Rows.Add(totalRowId);
    var totRow = dataGridBug.Rows[totRowPos];

    //Adding data to total row
    for (var c = 1; c < dataGridBug.ColumnCount; c++)
    {
        var sum = 0;
        for (var i = 0; i < dataGridBug.Rows.Count; ++i)
        {
            sum += Convert.ToInt32(dataGridBug.Rows[i].Cells[c].Value);
        }
        dataGridBug.Rows[totRowPos].Cells[c].Value = sum;
    }

    //Styling total column
    totCol.DefaultCellStyle.BackColor = gridBackColor;
    totCol.DefaultCellStyle.Font = gridFontStyle;

    //Styling total row
    totRow.DefaultCellStyle.BackColor = gridBackColor;
    totRow.DefaultCellStyle.Font = gridFontStyle;
}

数据网格中的输出看起来像

Answer 1

你可以这样做（它是动态解决方案，你不需要硬编码任何东西）。 Details类的BugModel属性包含所有列 Critical ， High 等等：

public class BugModel
{
    public string BugState { get; set; }
    public Dictionary<string, int> Details { get; set; }
    public int Total { get { return Details.Sum(x => x.Value); } }
}

<强>解决方案：

var result = (from bug in BugListGroup
              group bug by bug.BugState into sub
              select new BugModel
              {
                  BugState = sub.Key,
                  Details = sub.GroupBy(x => x.BugSeverity)
                             .ToDictionary(x => x.Key, x => x.Sum(y => y.BugCount))
              }).ToList();

Answer 2

我做过双重分组：

class Program
{
    internal class BugDetails
    {
        public int Id { get; set; }
        public string State { get; set; }
        public string Severity { get; set; }
    }
    static void Main(string[] args)
    {
        var MyBugList = new BugDetails[]
        {
            new BugDetails() { Id = 1, State = "Active", Severity = "Critical" },
            new BugDetails() { Id = 1, State = "Closed", Severity = "Critical" },
            new BugDetails() { Id = 1, State = "Closed", Severity = "Critical" },
            new BugDetails() { Id = 1, State = "Closed", Severity = "Critical" },
            new BugDetails() { Id = 1, State = "Resolved", Severity = "Critical" },
            new BugDetails() { Id = 1, State = "Resolved", Severity = "Critical" },
            new BugDetails() { Id = 1, State = "Resolved", Severity = "Critical" },

            new BugDetails() { Id = 1, State = "Active", Severity = "Medium" },
            new BugDetails() { Id = 1, State = "Active", Severity = "Medium" },
            new BugDetails() { Id = 1, State = "Closed", Severity = "Medium" },
            new BugDetails() { Id = 1, State = "Closed", Severity = "Medium" },
            new BugDetails() { Id = 1, State = "Resolved", Severity = "Medium" },
            new BugDetails() { Id = 1, State = "Resolved", Severity = "Medium" },
            new BugDetails() { Id = 1, State = "Resolved", Severity = "Medium" },

            new BugDetails() { Id = 1, State = "Active", Severity = "High" },
            new BugDetails() { Id = 1, State = "Active", Severity = "High" },
            new BugDetails() { Id = 1, State = "Closed", Severity = "High" },
            new BugDetails() { Id = 1, State = "Closed", Severity = "High" },
            new BugDetails() { Id = 1, State = "Closed", Severity = "High" },
            new BugDetails() { Id = 1, State = "Closed", Severity = "High" },
            new BugDetails() { Id = 1, State = "Closed", Severity = "High" },
        };

        var grouped = MyBugList.GroupBy(b => b.State).
            Select(stateGrp => stateGrp.GroupBy(b => b.Severity));

        foreach (var state in grouped)
        {
            Console.Write("{0}: ", state.First().First().State);
            foreach (var severity in state)
            {
                Console.Write("{0}={1} ", severity.Key, severity.Count());
            }
            Console.WriteLine();
        }
    }
}

输出：

Active: Critical=1 Medium=2 High=2
Closed: Critical=3 Medium=2 High=5
Resolved: Critical=3 Medium=3

如果要使用DataGridView显示数据在这种情况下，您可以使用自己的属性集动态创建类型。但这种方式很复杂。最简单（也是更多性能）的方法是手动填充DataGridView：

private void button1_Click(object sender, EventArgs e)
{
    var grouped = MyBugList.GroupBy(b => b.State).
        Select(stateGrp => stateGrp.GroupBy(b => b.Severity));

    dataGridView1.Columns.Add("State", "State");
    foreach (var strSeverity in MyBugList.Select(b => b.Severity).Distinct())
        dataGridView1.Columns.Add(strSeverity, strSeverity);

    foreach (var state in grouped)
    {
        int nRow = dataGridView1.Rows.Add();
        dataGridView1.Rows[nRow].Cells[0].Value = state.First().First().State;
        foreach (var severity in state)
        {
            dataGridView1.Rows[nRow].Cells[severity.Key].Value = severity.Count();
        }
    }
}

结果：

LINQ查询对象列表以获取基于多个字段的分布

2 个答案: