Xceed DataGrid重复记录点击自定义筛选按钮崩溃问题求助

Hey there, sorry to hear you're hitting this frustrating crash with the Xceed DataGrid's custom filter dropdown when duplicate datetime records are present. Let's walk through some actionable steps to diagnose and fix this issue:

1. Pinpoint the Crash Source with Debug Tools #

First, let's stop guessing and find exactly where the crash happens:

• Enable full exception catching in Visual Studio: Go to Debug > Windows > Exception Settings, then check "Common Language Runtime Exceptions". When the crash occurs, the debugger will break directly at the line causing the error, and you can inspect the call stack to see which method is failing.
• If you're using a wrapped XceedGridControl, check your XceedGridWrapper class for any overridden methods or event handlers related to filtering—look for names like OnFilterButtonClicked, FilterOpening, or HandleFilterRequest. The wrapper might be handling the dropdown trigger logic internally.

2. Check for Duplicate Value Handling in Filter Logic #

The crash is likely tied to the duplicate datetime values not being handled properly in the filter's dropdown data:

• If you're using a custom filter template (defined in XAML for your column), verify that the dropdown's ItemsSource is pulling from a deduplicated set of datetime values. Xceed's default filter dropdowns automatically handle duplicates, but custom templates often require manual deduplication.
• Test with a quick fix: Temporarily modify your binding source to exclude duplicates to see if the crash stops:

  var dataProviderBinding = new Binding 
  { 
      Source = Presenter.OriginalMeasurementRecords.DistinctBy(x => x.YourDateTimeProperty), 
      Mode = BindingMode.OneWay 
  };
  dataGridControl.SetBinding(XceedGridWrapper.DataProviderProperty, dataProviderBinding);
  

  Replace YourDateTimeProperty with the actual datetime field in your records. If the crash goes away, you've confirmed the duplicate values are the root cause.

3. Inspect the XceedGridWrapper's DataProvider Logic #

Since you're binding to a custom DataProviderProperty via XceedGridWrapper, this wrapper might be introducing the issue:

• Look for code in the wrapper that processes the source data to generate filter options. Does it assume unique values when building the dropdown list? For example, if it's using a HashSet without a proper equality comparer for datetime values, or trying to sort a list with duplicate entries in a way that throws an exception.
• Ensure the wrapper isn't modifying the source collection in a thread-unsafe way when the filter dropdown is opened—race conditions could also cause crashes, especially with duplicate data.

4. Verify DateTime Equality Handling #

Datetime values can sometimes have hidden precision differences (like milliseconds or ticks) that make them appear duplicate but aren't. Check if your equality checks for datetime values are accounting for this:

• If you're using Distinct(), make sure you're using a comparer that ignores irrelevant precision. For example:

  public class DateTimeEqualityComparer : IEqualityComparer<YourRecordType>
  {
      public bool Equals(YourRecordType x, YourRecordType y)
      {
          // Compare datetime values up to seconds, ignoring milliseconds
          return x.DateTimeField.Date == y.DateTimeField.Date &&
                 x.DateTimeField.Hour == y.DateTimeField.Hour &&
                 x.DateTimeField.Minute == y.DateTimeField.Minute &&
                 x.DateTimeField.Second == y.DateTimeField.Second;
      }
  
      public int GetHashCode(YourRecordType obj)
      {
          return obj.DateTimeField.ToString("yyyyMMddHHmmss").GetHashCode();
      }
  }
  

  Then use it like: OriginalMeasurementRecords.Distinct(new DateTimeEqualityComparer())

If you can share more details—like the XAML for your custom filter dropdown, or the code in XceedGridWrapper related to filtering—I can help narrow this down further!

内容的提问来源于stack exchange，提问作者AidanH