通过

ChildView 和关系

如果 DataSet 中的表之间存在关系，则可以使用 DataView 的 CreateChildView 方法为父表中的行创建一个 DataRowView，包含相关子表中的行。 例如，下面的代码按字母顺序显示 Categories 及其相关 Products，并按照 CategoryName 和 ProductName 排序。

Dim catTable As DataTable = catDS.Tables("Categories")
Dim prodTable As DataTable = catDS.Tables("Products")

' Create a relation between the Categories and Products tables.
Dim relation As DataRelation = catDS.Relations.Add("CatProdRel", _
  catTable.Columns("CategoryID"), _
  prodTable.Columns("CategoryID"))

' Create DataViews for the Categories and Products tables.
Dim catView As DataView = New DataView(catTable, "", _
  "CategoryName", DataViewRowState.CurrentRows)
Dim prodView As DataView

' Iterate through the Categories table.
Dim catDRV, prodDRV As DataRowView

For Each catDRV In catView
  Console.WriteLine(catDRV("CategoryName"))

  ' Create a DataView of the child product records.
  prodView = catDRV.CreateChildView(relation)
  prodView.Sort = "ProductName"

  For Each prodDRV In prodView
    Console.WriteLine(vbTab & prodDRV("ProductName"))
  Next
Next

DataTable catTable = catDS.Tables["Categories"];
DataTable prodTable = catDS.Tables["Products"];

// Create a relation between the Categories and Products tables.
DataRelation relation = catDS.Relations.Add("CatProdRel",
  catTable.Columns["CategoryID"],
                                                            prodTable.Columns["CategoryID"]);

// Create DataViews for the Categories and Products tables.
DataView catView = new DataView(catTable, "", "CategoryName",
  DataViewRowState.CurrentRows);
DataView prodView;

// Iterate through the Categories table.
foreach (DataRowView catDRV in catView)
{
  Console.WriteLine(catDRV["CategoryName"]);

  // Create a DataView of the child product records.
  prodView = catDRV.CreateChildView(relation);
  prodView.Sort = "ProductName";

  foreach (DataRowView prodDRV in prodView)
    Console.WriteLine("\t" + prodDRV["ProductName"]);
}

另请参阅

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