按布爾分組會產生錯誤的結果-有解無憂

我正在嘗試使用 LiveCharts 庫在圖表中可視化資料庫中的資料。我設法讓其中一些作業正常。但是我在使用 PieCharts 時遇到了困難。我想簡單地在兩個切片中顯示資料。為此，我在 DB 中有名為 AppIsRunning 的列。

我做了一個簡單的例子，它作業正常并按預期在切片中顯示資料：

  List<DataModel> records = new List<DataModel>();

  records.Add(new DataModel { Id = 1, Revenue = 43, Name = "Item 1", AppIsRunning = true });
  records.Add(new DataModel { Id = 2, Revenue = 23, Name = "Item 2", AppIsRunning = true });
  records.Add(new DataModel { Id = 3, Revenue = 13, Name = "Item 3", AppIsRunning = true });
  records.Add(new DataModel { Id = 4, Revenue = 87, Name = "Item 4", AppIsRunning = true });
  records.Add(new DataModel { Id = 5, Revenue = 23, Name = "Item 5", AppIsRunning = true });

  IEnumerable<ISeries> result1 = records.Select(x =>
    new PieSeries<double>
    {
      Values = new List<double> { x.Revenue },
      Name = x.Name,
    });

按布爾分組會產生錯誤的結果

現在我想對資料進行分組以僅顯示 2 個切片 AppIsRunning true/false，并且對于 Values 有收入。所以我最終得到了這段代碼：

  List<DataModel> records = new List<DataModel>();

  records.Add(new DataModel { Id = 1, Revenue = 43, Name = "Item 1", AppIsRunning = true });
  records.Add(new DataModel { Id = 2, Revenue = 23, Name = "Item 2", AppIsRunning = true });
  records.Add(new DataModel { Id = 3, Revenue = 13, Name = "Item 3", AppIsRunning = false });
  records.Add(new DataModel { Id = 4, Revenue = 87, Name = "Item 4", AppIsRunning = true });
  records.Add(new DataModel { Id = 5, Revenue = 23, Name = "Item 5", AppIsRunning = true });

  IEnumerable<ISeries> result1 = records
        .GroupBy(g => g.AppIsRunning)
        .Select(item => new PieSeries<double>
        {
          Values = item.Select(x => Convert.ToDouble(x.Revenue)),
          Name = item.Key ? "Running" : "Not running",
        });

然而，這使得 AppIsRunning true 部分分為 4 個子切片 = 4 AppIsRunning TRUE 值。請參閱藍色切片中包含 4 個子部分的螢屏截圖：

按布爾分組會產生錯誤的結果

我的問題是如何擺脫這 4 個子部分并將這些資料分組為一個？我只需要 2 個切片，不需要將切片分成小節。

Here is original example from LiveCharts:

  this.ActivityChartSeries = new ISeries[]
  {
    new PieSeries<double> { Values = new double[] { 2 }, Name = "Section 1"},
    new PieSeries<double> { Values = new double[] { 21 }, Name = "Section 2"},
    new PieSeries<double> { Values = new double[] { 28 }, Name = "Section 3"},
    new PieSeries<double> { Values = new double[] { 2 }, Name = "Section 4"},
    new PieSeries<double> { Values = new double[] { 52 }, Name = "Section 5"},
  };

https://github.com/beto-rodriguez/LiveCharts2/blob/master/samples/ViewModelsSamples/Pies/Basic/ViewModel.cs

uj5u.com熱心網友回復：

從示例來看，您希望將總收入（總和）細分為每個狀態的單個值。為此，您可以這樣做：

IEnumerable<ISeries> result1 = records
    .GroupBy(g => g.AppIsRunning)
    .Select(item => new PieSeries<double>
    {
      Values = new List<double> {item.Sum(x => Convert.ToDouble(x.Revenue))},
      Name = item.Key ? "Running" : "Not running",
    });

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標籤：c# linq livecharts

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