DataTable.Select DataTable.Select DataTable.Select DataTable.Select Method

定義

取得 DataRow 物件的陣列。Gets an array of DataRow objects.

多載

Select() Select() Select() Select()

取得所有 DataRow 物件的陣列。Gets an array of all DataRow objects.

Select(String) Select(String) Select(String) Select(String)

取得所有符合篩選準則之 DataRow 物件的陣列。Gets an array of all DataRow objects that match the filter criteria.

Select(String, String) Select(String, String) Select(String, String) Select(String, String)

取得按照指定排序順序符合篩選條件的所有 DataRow 物件之陣列。Gets an array of all DataRow objects that match the filter criteria, in the specified sort order.

Select(String, String, DataViewRowState) Select(String, String, DataViewRowState) Select(String, String, DataViewRowState) Select(String, String, DataViewRowState)

取得符合篩選條件 (按照排序順序,並符合指定狀態) 的所有 DataRow 物件之陣列。Gets an array of all DataRow objects that match the filter in the order of the sort that match the specified state.

Select() Select() Select() Select()

取得所有 DataRow 物件的陣列。Gets an array of all DataRow objects.

public:
 cli::array <System::Data::DataRow ^> ^ Select();
public System.Data.DataRow[] Select ();
member this.Select : unit -> System.Data.DataRow[]
Public Function Select () As DataRow()

傳回

DataRow 物件的陣列。An array of DataRow objects.

範例

下列範例會Select透過方法傳回物件DataRow的陣列。The following example returns an array of DataRow objects through the Select method.

private void GetRows()
{
    // Get the DataTable of a DataSet.
    DataTable table = DataSet1.Tables["Suppliers"];
    DataRow[] rows = table.Select();

    // Print the value one column of each DataRow.
    for(int i = 0; i < rows.Length ; i++)
    {
        Console.WriteLine(rows[i]["CompanyName"]);
    }
}
Private Sub GetRows()
    ' Get the DataTable of a DataSet.
    Dim table As DataTable = DataSet1.Tables("Suppliers")
    Dim rows() As DataRow = table.Select()

    Dim i As Integer
    ' Print the value one column of each DataRow.
    For i = 0 to rows.GetUpperBound(0)
       Console.WriteLine(rows(i)("CompanyName"))
    Next i
End Sub

備註

若要確保適當的排序次序,請使用Select(String, String)Select(String, String, DataViewRowState)指定排序準則。To ensure the proper sort order, specify sort criteria with Select(String, String) or Select(String, String, DataViewRowState).

另請參閱

Select(String) Select(String) Select(String) Select(String)

取得所有符合篩選準則之 DataRow 物件的陣列。Gets an array of all DataRow objects that match the filter criteria.

public:
 cli::array <System::Data::DataRow ^> ^ Select(System::String ^ filterExpression);
public System.Data.DataRow[] Select (string filterExpression);
member this.Select : string -> System.Data.DataRow[]
Public Function Select (filterExpression As String) As DataRow()

參數

filterExpression
String String String String

用來篩選資料列的準則。The criteria to use to filter the rows. 如需如何篩選資料列的範例,請參閱 DataView RowFilter Syntax [C#] (DataView RowFilter 語法 [C#])。For examples on how to filter rows, see DataView RowFilter Syntax [C#].

傳回

DataRow 物件的陣列。An array of DataRow objects.

範例

下列範例會使用篩選運算式來傳回物件的DataRow陣列。The following example uses a filter expression to return an array of DataRow objects.

private void GetRowsByFilter()
{
    DataTable table = DataSet1.Tables["Orders"];
    // Presuming the DataTable has a column named Date.
    string expression;
    expression = "Date > #1/1/00#";
    DataRow[] foundRows;

    // Use the Select method to find all rows matching the filter.
    foundRows = table.Select(expression);

    // Print column 0 of each returned row.
    for(int i = 0; i < foundRows.Length; i ++)
    {
        Console.WriteLine(foundRows[i][0]);
    }
}
Private Sub GetRowsByFilter()
    
    Dim table As DataTable = DataSet1.Tables("Orders")

    ' Presuming the DataTable has a column named Date.
    Dim expression As String
    expression = "Date > #1/1/00#"
    Dim foundRows() As DataRow

    ' Use the Select method to find all rows matching the filter.
    foundRows = table.Select(expression)

    Dim i As Integer
    ' Print column 0 of each returned row.
    For i = 0 to foundRows.GetUpperBound(0)
       Console.WriteLine(foundRows(i)(0))
    Next i
End Sub

備註

若要建立filterExpression引數,請使用與DataColumn類別的Expression屬性值相同的規則來建立篩選。To create the filterExpression argument, use the same rules that apply to the DataColumn class's Expression property value for creating filters.

若要確保適當的排序次序,請使用Select(String, String)Select(String, String, DataViewRowState)指定排序準則。To ensure the proper sort order, specify sort criteria with Select(String, String) or Select(String, String, DataViewRowState).

如果篩選準則中的資料行包含 null 值,它就不會是結果的一部分。If the column on the filter contains a null value, it will not be part of the result.

另請參閱

Select(String, String) Select(String, String) Select(String, String) Select(String, String)

取得按照指定排序順序符合篩選條件的所有 DataRow 物件之陣列。Gets an array of all DataRow objects that match the filter criteria, in the specified sort order.

public:
 cli::array <System::Data::DataRow ^> ^ Select(System::String ^ filterExpression, System::String ^ sort);
public System.Data.DataRow[] Select (string filterExpression, string sort);
member this.Select : string * string -> System.Data.DataRow[]
Public Function Select (filterExpression As String, sort As String) As DataRow()

參數

filterExpression
String String String String

用來篩選資料列的準則。The criteria to use to filter the rows. 如需如何篩選資料列的範例,請參閱 DataView RowFilter Syntax [C#] (DataView RowFilter 語法 [C#])。For examples on how to filter rows, see DataView RowFilter Syntax [C#].

sort
String String String String

指定資料行和排序方向的字串。A string specifying the column and sort direction.

傳回

符合篩選條件運算式的 DataRow 物件之陣列。An array of DataRow objects matching the filter expression.

範例

下列範例會使用篩選運算式來傳回物件的DataRow陣列。The following example uses a filter expression to return an array of DataRow objects.

using System;
using System.Data;

public class A {  

   public static void Main() {      
      DataTable table = new DataTable("Orders");
      table.Columns.Add("OrderID", typeof(Int32));
      table.Columns.Add("OrderQuantity", typeof(Int32));
      table.Columns.Add("CompanyName", typeof(string));      
      table.Columns.Add("Date", typeof(DateTime));

      DataRow newRow = table.NewRow();
      newRow["OrderID"] = 1;
      newRow["OrderQuantity"] = 3;
      newRow["CompanyName"] = "NewCompanyName";
      newRow["Date"] = "1979, 1, 31";

      // Add the row to the rows collection.
      table.Rows.Add(newRow);
      
      DataRow newRow2 = table.NewRow();
      newRow2["OrderID"] = 2;
      newRow2["OrderQuantity"] = 2;
      newRow2["CompanyName"] = "NewCompanyName1";
      table.Rows.Add(newRow2);

      DataRow newRow3 = table.NewRow();
      newRow3["OrderID"] = 3;
      newRow3["OrderQuantity"] = 2;
      newRow3["CompanyName"] = "NewCompanyName2";
      table.Rows.Add(newRow3);

      // Presuming the DataTable has a column named Date.
      string expression = "Date = '1/31/1979' or OrderID = 2";
      // string expression = "OrderQuantity = 2 and OrderID = 2";

      // Sort descending by column named CompanyName.
      string sortOrder = "CompanyName ASC";
      DataRow[] foundRows;

      // Use the Select method to find all rows matching the filter.
      foundRows = table.Select(expression, sortOrder);

      // Print column 0 of each returned row.
      for (int i = 0; i < foundRows.Length; i++)
         Console.WriteLine(foundRows[i][2]);
   }
}
Imports System.Data

Public Class A

   Public Shared Sub Main()
      Dim table As New DataTable("Orders")
      table.Columns.Add("OrderID", GetType(Int32))
      table.Columns.Add("OrderQuantity", GetType(Int32))
      table.Columns.Add("CompanyName", GetType(String))
      table.Columns.Add("Date", GetType(DateTime))

      Dim newRow As DataRow = table.NewRow()
      newRow("OrderID") = 1
      newRow("OrderQuantity") = 3
      newRow("CompanyName") = "NewCompanyName"
      newRow("Date") = "1979, 1, 31"

      ' Add the row to the rows collection.
      table.Rows.Add(newRow)

      Dim newRow2 As DataRow = table.NewRow()
      newRow2("OrderID") = 2
      newRow2("OrderQuantity") = 2
      newRow2("CompanyName") = "NewCompanyName1"
      table.Rows.Add(newRow2)

      Dim newRow3 As DataRow = table.NewRow()
      newRow3("OrderID") = 3
      newRow3("OrderQuantity") = 2
      newRow3("CompanyName") = "NewCompanyName2"
      table.Rows.Add(newRow3)

      ' Presuming the DataTable has a column named Date.
      Dim expression As String = "Date = '1/31/1979' or OrderID = 2"
      ' Dim expression As String = "OrderQuantity = 2 and OrderID = 2"

      ' Sort descending by column named CompanyName.
      Dim sortOrder As String = "CompanyName ASC"
      Dim foundRows As DataRow()

      ' Use the Select method to find all rows matching the filter.
      foundRows = table.[Select](expression, sortOrder)

      ' Print column 0 of each returned row.
      For i As Integer = 0 To foundRows.Length - 1
         Console.WriteLine(foundRows(i)(2))
      Next
   End Sub
End Class

備註

若要形成filterExpression引數,請使用相同的規則來DataColumn建立類別Expression的屬性值。To form the filterExpression argument, use the same rules for creating the DataColumn class's Expression property value. 引數也會使用相同的規則來建立類別Expression的字串。 SortThe Sort argument also uses the same rules for creating class's Expression strings.

如果篩選準則中的資料行包含 null 值,它就不會是結果的一部分。If the column on the filter contains a null value, it will not be part of the result.

另請參閱

Select(String, String, DataViewRowState) Select(String, String, DataViewRowState) Select(String, String, DataViewRowState) Select(String, String, DataViewRowState)

取得符合篩選條件 (按照排序順序,並符合指定狀態) 的所有 DataRow 物件之陣列。Gets an array of all DataRow objects that match the filter in the order of the sort that match the specified state.

public:
 cli::array <System::Data::DataRow ^> ^ Select(System::String ^ filterExpression, System::String ^ sort, System::Data::DataViewRowState recordStates);
public System.Data.DataRow[] Select (string filterExpression, string sort, System.Data.DataViewRowState recordStates);
member this.Select : string * string * System.Data.DataViewRowState -> System.Data.DataRow[]
Public Function Select (filterExpression As String, sort As String, recordStates As DataViewRowState) As DataRow()

參數

filterExpression
String String String String

用來篩選資料列的準則。The criteria to use to filter the rows. 如需如何篩選資料列的範例,請參閱 DataView RowFilter Syntax [C#] (DataView RowFilter 語法 [C#])。For examples on how to filter rows, see DataView RowFilter Syntax [C#].

sort
String String String String

指定資料行和排序方向的字串。A string specifying the column and sort direction.

傳回

DataRow 物件的陣列。An array of DataRow objects.

範例

下列範例會使用篩選運算式和記錄狀態來傳回物件的DataRow陣列。The following example uses a filter expression and record state to return an array of DataRow objects.

private static void GetRowsByFilter()
{
    DataTable customerTable = new DataTable("Customers");
    // Add columns
    customerTable.Columns.Add("id", typeof(int));
    customerTable.Columns.Add("name", typeof(string));

    // Set PrimaryKey
    customerTable.Columns[ "id" ].Unique = true;
    customerTable.PrimaryKey = new DataColumn[] 
        { customerTable.Columns["id"] };

    // Add ten rows
    for(int id=1; id<=10; id++)
    {
        customerTable.Rows.Add(
            new object[] { id, string.Format("customer{0}", id) });
    }
    customerTable.AcceptChanges();

    // Add another ten rows
    for(int id=11; id<=20; id++)
    {
        customerTable.Rows.Add(
            new object[] { id, string.Format("customer{0}", id) });
    }

    string expression;
    string sortOrder;

    expression = "id > 5";
    // Sort descending by column named CompanyName.
    sortOrder = "name DESC";
    // Use the Select method to find all rows matching the filter.
    DataRow[] foundRows = 
        customerTable.Select(expression, sortOrder, 
        DataViewRowState.Added);

    PrintRows(foundRows, "filtered rows");

    foundRows = customerTable.Select();
    PrintRows(foundRows, "all rows");
}

private static void PrintRows(DataRow[] rows, string label)
{
    Console.WriteLine("\n{0}", label);
    if(rows.Length <= 0)
    {
        Console.WriteLine("no rows found");
        return;
    }
    foreach(DataRow row in rows)
    {
        foreach(DataColumn column in row.Table.Columns)
        {
            Console.Write("\table {0}", row[column]);
        }
        Console.WriteLine();
    }
}
Private Sub GetRowsByFilter()

    Dim customerTable As New DataTable("Customers")

    ' Add columns
    customerTable.Columns.Add("id", GetType(Integer))
    customerTable.Columns.Add("name", GetType(String))

    ' Set PrimaryKey
    customerTable.Columns("id").Unique = True
    customerTable.PrimaryKey = New DataColumn() _
        {customerTable.Columns("id")}

    ' add ten rows
    Dim id As Integer
    For id = 1 To 10
        customerTable.Rows.Add( _
        New Object() {id, String.Format("customer{0}", id)})
    Next id
    customerTable.AcceptChanges()

    ' add another ten rows
    For id = 11 To 20
        customerTable.Rows.Add( _
        New Object() {id, String.Format("customer{0}", id)})
    Next id

    Dim expression As String
    Dim sortOrder As String

    expression = "id > 5"
    ' Sort descending by CompanyName column.
    sortOrder = "name DESC"

    ' Use the Select method to find all rows matching the filter.
    Dim foundRows As DataRow() = _
        customerTable.Select(expression, sortOrder, _
        DataViewRowState.Added)

    PrintRows(foundRows, "filtered rows")

    foundRows = customerTable.Select()
    PrintRows(foundRows, "all rows")
End Sub

Private Sub PrintRows(ByVal rows() As DataRow, ByVal label As String)
    Console.WriteLine("\n{0}", label)
    If rows.Length <= 0 Then
        Console.WriteLine("no rows found")
        Exit Sub
    End If

    Dim row As DataRow
    Dim column As DataColumn
    For Each row In rows
        For Each column In row.Table.Columns
            Console.Write("\table {0}", row(column))
        Next column
        Console.WriteLine()
    Next row
End Sub

備註

若要形成filterExpression引數,請使用相同的規則來DataColumn建立類別Expression的屬性值。To form the filterExpression argument, use the same rules for creating the DataColumn class's Expression property value. 引數也會使用相同的規則來建立類別Expression的字串。 SortThe Sort argument also uses the same rules for creating class's Expression strings.

如果篩選準則中的資料行包含 null 值,它就不會是結果的一部分。If the column on the filter contains a null value, it will not be part of the result.

另請參閱

適用於