BindingSource.Count 属性

定义

命名空间:

System.Windows.Forms

程序集:

System.Windows.Forms.dll

获取在的基础列表中项的总数。获取在基础列表中项的总数，考虑当前 Filter 值。

public:
 virtual property int Count { int get(); };

[System.ComponentModel.Browsable(false)]
public virtual int Count { get; }

[<System.ComponentModel.Browsable(false)>]
member this.Count : int

Public Overridable ReadOnly Property Count As Integer

属性值

Int32

基础列表中筛选项的总项数。

实现

Count

属性

BrowsableAttribute

示例

以下代码示例演示 、 ListRemoveAt和 Count 成员。 若要运行此示例，请将代码粘贴到一个窗体中，其中包含一BindingSource1个名为 、两个名为 label1BindingSource 和 label2的标签以及一个名为 的button1按钮。 将 button1_Click 方法与 Click 的事件 button1相关联。 Visual Basic 用户需要添加对 System.Data.dll 的引用。

private void button1_Click(object sender, EventArgs e)
{
    // Create the connection string, data adapter and data table.
    SqlConnection connectionString =
         new SqlConnection("Initial Catalog=Northwind;" +
         "Data Source=localhost;Integrated Security=SSPI;");
    SqlDataAdapter customersTableAdapter =
        new SqlDataAdapter("Select * from Customers", connectionString);
    DataTable customerTable = new DataTable();

    // Fill the adapter with the contents of the customer table.
    customersTableAdapter.Fill(customerTable);

    // Set data source for BindingSource1.
    BindingSource1.DataSource = customerTable;

    // Set the label text to the number of items in the collection before
    // an item is removed.
    label1.Text = "Starting count: " + BindingSource1.Count.ToString();

    // Access the List property and remove an item.
    BindingSource1.List.RemoveAt(4);

    // Remove an item directly from the BindingSource. 
    // This is equivalent to the previous line of code.
    BindingSource1.RemoveAt(4);

    // Show the new count.
    label2.Text = "Count after removal: " + BindingSource1.Count.ToString();
}

    Private Sub button1_Click(ByVal sender As Object, ByVal e As EventArgs) _
        Handles button1.Click

        ' Create the connection string, data adapter and data table.
        Dim connectionString As New SqlConnection("Initial Catalog=Northwind;" & _
            "Data Source=localhost;Integrated Security=SSPI;")
        Dim customersTableAdapter As New SqlDataAdapter("Select * from Customers", _
            connectionString)
        Dim customerTable As New DataTable()

        ' Fill the adapter with the contents of the customer table.
        customersTableAdapter.Fill(customerTable)

        ' Set data source for BindingSource1.
        BindingSource1.DataSource = customerTable

        ' Set the label text to the number of items in the collection before
        ' an item is removed.
        label1.Text = "Starting count: " + BindingSource1.Count.ToString()

        ' Access the List property and remove an item.
        BindingSource1.List.RemoveAt(4)

        ' Remove an item directly from the BindingSource. 
        ' This is equivalent to the previous line of code.
        BindingSource1.RemoveAt(4)

        ' Show the new count.
        label2.Text = "Count after removal: " + BindingSource1.Count.ToString()

    End Sub
End Class

注解

属性 Count 获取由 属性表示 List 的基础列表中由 属性的值修改的 Filter 项数。

另请参阅

• List
• Position
• Current