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"ChildViews ve İlişkiler"

Tablolar arasında bir ilişki olduğu durumlarda, üst tablodaki satırlar için DataSet yöntemini kullanarak, ilgili alt tablodan gelen satırları içeren bir DataView oluşturabilirsiniz CreateChildView. Örneğin, aşağıdaki kod Categories ve ilgili olanları Products ölçütü ve ProductName'e göre alfabetik olarak sıralanmış şekilde görüntüler.

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"]);
}

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