BindingSource.RemoveAt(Int32) 方法
定义
重要
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移除此列表中指定索引处的项。
public:
virtual void RemoveAt(int index);public virtual void RemoveAt (int index);abstract member RemoveAt : int -> unit
override this.RemoveAt : int -> unitPublic Overridable Sub RemoveAt (index As Integer)参数
- index
- Int32
要移除的项的从零开始的索引。
实现
例外
index 小于零或大于 Count 属性的值。
由 List 属性表示的基础列表为只读或具有固定大小。
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
这两个条件可以分别使用 IsFixedSize 和 IsReadOnly 属性进行测试。
此方法引发 ListChanged 事件。
