DataGridVIew填充了匿名类型,如何过滤?

时间:2010-12-01 06:24:44

标签: c# linq datagridview datasource anonymous-types

我使用LINQ查询填充了DataGridView,该查询返回匿名类型。

问题:是否有机会过滤其数据源实际上是匿名的DataGridView?

// Setting the datagridview data source
rawDocumentsDataGridView.DataSource = rawTopics
    .SelectMany(t => t.Documents)
        .Select(d => new
            {
               DocumentId = d.Id,
               Rilevante = d.IsRelevant,
               TopicId = d.Topic.Id // foreign key
            }).ToList();

// Make it not visibile, waiting for master change
rawDocumentsDataGridView.Visible = false;

// When master selection changed...
void rawTopicsDataGridView_SelectionChanged(object sender, System.EventArgs e)
{
    if (rawTopicsDataGridView.CurrentRow == null) return;

    // Get selected topic id
    int tid = (int) rawTopicsDataGridView.CurrentRow.Cells["TopicId"].Value;

    // Filter rawDocumentsDataGridView based on topic id
    // WARNING: PSEUDO CODE
    var oldDataSource = (List<AnonymousType>)rawDocumentsDataGridView.DataSource;
    rawDocumentsDataGridView.DataSource = oldDataSource
       .Where(d => d.TopicId == tid);
}

1 个答案:

答案 0 :(得分:7)

如果你继续这样做(释义)“DataSource = DataSource.Where(...)”你将反复过滤里面过滤后的数据;但在这种情况下,我会:

a:将列表存储在字段中以便重复使用,

b:不是我们的匿名类型

class DocumentRow {
    public int DocumentId {get;set;}
    public bool Rilevante {get;set;}
    public int TopicId {get;set;}
}
...
List<DocumentRow> allData;
...
allData = rawTopics.SelectMany(t => t.Documents)
    .Select(d => new DocumentRow
        {
           DocumentId = d.Id,
           Rilevante = d.IsRelevant,
           TopicId = d.Topic.Id // foreign key
        }).ToList();
...
rawDocumentsDataGridView.DataSource = allData
   .Where(d => d.TopicId == tid).ToList();