DataColumnCollection.Item[] 屬性

來源:

DataColumnCollection.cs

來源:

DataColumnCollection.cs

來源:

DataColumnCollection.cs

來源:

DataColumnCollection.cs

來源:

DataColumnCollection.cs

public:
 property System::Data::DataColumn ^ default[int] { System::Data::DataColumn ^ get(int index); };

public:
 virtual property System::Data::DataColumn ^ default[int] { System::Data::DataColumn ^ get(int index); };

public System.Data.DataColumn this[int index] { get; }

public virtual System.Data.DataColumn this[int index] { get; }

member this.Item(int) : System.Data.DataColumn

Default Public ReadOnly Property Item(index As Integer) As DataColumn

Default Public Overridable ReadOnly Property Item(index As Integer) As DataColumn

參數

屬性值

在指定的索引上。DataColumn

例外狀況

範例

以下範例使用該 Item[] 屬性來列印 ColumnName 由索引指定的物件值 DataColumn 。 範例中使用由系統包含的 DataTable。Windows。Forms.DataGrid 控制。

private void PrintColumnNamesByIndex(DataTable table)
{
    // Get the DataColumnCollection from a DataTable in a DataSet.
    DataColumnCollection columns = table.Columns;

    // Print each column's name using the Index.
    for (int i = 0 ;i <columns.Count ;i++)
        Console.WriteLine(columns[i]);
}

Private Sub PrintColumnNamesByIndex(table As DataTable)
    ' Get the DataColumnCollection from a DataTable in a DataSet.
    Dim columns As DataColumnCollection = table.Columns

    ' Print each column's name using the Index.
    Dim i As Integer
    For i = 0 To columns.Count - 1
        Console.WriteLine(columns(i))
    Next i
End Sub

備註

此 Contains 方法可用於檢測欄位的存在。 在你嘗試使用 Item[]之前，這很有用。

另請參閱

• ColumnName
• Contains(String)
• DataColumn

來源:

DataColumnCollection.cs

來源:

DataColumnCollection.cs

來源:

DataColumnCollection.cs

來源:

DataColumnCollection.cs

來源:

DataColumnCollection.cs

public:
 property System::Data::DataColumn ^ default[System::String ^] { System::Data::DataColumn ^ get(System::String ^ name); };

public:
 virtual property System::Data::DataColumn ^ default[System::String ^] { System::Data::DataColumn ^ get(System::String ^ name); };

public System.Data.DataColumn? this[string name] { get; }

public System.Data.DataColumn this[string name] { get; }

public virtual System.Data.DataColumn this[string name] { get; }

member this.Item(string) : System.Data.DataColumn

Default Public ReadOnly Property Item(name As String) As DataColumn

Default Public Overridable ReadOnly Property Item(name As String) As DataColumn

參數

屬性值

在指定的DataColumn集合中 ;ColumnName否則若不存在，DataColumn則為空值。

範例

以下範例使用該 Item[] 屬性來列印 DataType 由索引指定的物件值 DataColumn 。

private void PrintDataType(DataTable table)
{
    // Get the DataColumnCollection from a DataTable in a DataSet.
    DataColumnCollection columns = table.Columns;

    // Print the column's data type.
    Console.WriteLine(columns["id"].DataType);
}

Private Sub PrintDataType(table As DataTable)
     ' Get the DataColumnCollection from a DataTable in a DataSet.
     Dim columns As DataColumnCollection = table.Columns

     ' Print the column's data type.
     Console.WriteLine(columns("id").DataType)
End Sub

備註

Item[] 當它搜尋欄位名稱時，是條件大小寫區分的。 例如，若一個 DataColumn 欄位名為「mydatacolumn」，另一個名為「Mydatacolumn」，則用於搜尋其中一個欄位的字串被視為大小寫區分。 然而，如果「mydatacolumn」存在而「Mydatacolumn」沒有，則該搜尋字串被視為不區分大小寫。

另請參閱

• ColumnName
• Contains(String)
• DataColumn