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ObjectDataSource自定義分頁
ObjectDataSource是唯一支持自定義分頁的數據源，要實現分頁效果，首先要將ObjectDataSource.EnablePageing屬性設為true，通過三個屬性實現：StartRowIndex,MaximumRows和SelectCountMethod，效果如圖：
實現分頁有兩種情況：一種是假分頁，一種是真分頁；
假分頁：就是將數據全部取出來，隻是分頁顯示，它不是分頁取數據，隻是分頁顯示。
真分頁：就是按需取數據，隻取出每一頁所需的數據；這裏是使用存儲過程做的是真分頁。
首先，最重要的是使用到的存儲過程：（以NorthWind數據庫為例）
ALTER PROCEDURE GetEmployeePage @Start int, @Count int AS -- 創建一張臨時表，增加ID屬性列。 CREATE TABLE #TempEmployees ( ID int IDENTITY PRIMARY KEY, EmployeeID int, LastName nvarchar(20), FirstName nvarchar(10), TitleOfCourtesy nvarchar(25), ) -- 用employees表的相關字段來填充臨時表。 INSERT INTO #TempEmployees ( EmployeeID, LastName, FirstName, TitleOfCourtesy ) SELECT EmployeeID, LastName, FirstName, TitleOfCourtesy FROM Employees ORDER BY EmployeeID ASC -- 聲明兩個變量來計算的記錄的範圍。 DECLARE @FromID int DECLARE @ToID int -- 計算我們需要的第一個和最後一個編號的各種記錄。 SET @FromID = @Start SET @ToID = @Start + @Count - 1 -- 查找一頁顯示的內容。 SELECT * FROM #TempEmployees WHERE ID >= @FromID AND ID <= @ToID
其次，就是調用存儲過程的數據訪問類：
public class EmployeesPager { public EmployeesPager() { } private string connectionString; public List<EmployeeDetails> GetEmployees(int startRowIndex, int maximumRows) { connectionString = WebConfigurationManager.ConnectionStrings["Northwind"].ConnectionString; SqlConnection con = new SqlConnection(connectionString); SqlCommand cmd = new SqlCommand("GetEmployeePage", con); cmd.CommandType = CommandType.StoredProcedure; cmd.Parameters.Add(new SqlParameter("@Start", SqlDbType.Int, 4)); cmd.Parameters["@Start"].Value = startRowIndex +1; cmd.Parameters.Add(new SqlParameter("@Count", SqlDbType.Int, 4)); cmd.Parameters["@Count"].Value = maximumRows; // Create a collection for all the employee records. List<EmployeeDetails> employees = new List<EmployeeDetails>(); try { con.Open(); SqlDataReader reader = cmd.ExecuteReader(); while (reader.Read()) { EmployeeDetails emp = new EmployeeDetails( (int)reader["EmployeeID"], (string)reader["FirstName"], (string)reader["LastName"], (string)reader["TitleOfCourtesy"]); employees.Add(emp); } reader.Close(); return employees; } catch (SqlException err) { // Replace the error with something less specific. // You could also log the error now. throw new ApplicationException("Data error."); } finally { con.Close(); } } }
最後，就是前台界麵調用這個訪問類的方法：
protected void Page_Load(object sender, EventArgs e) { EmployeesPager emp = new EmployeesPager(); GridView1.DataSource = emp.GetEmployees(0, 5);//默認顯示前5條記錄； GridView1.DataBind(); if (!IsPostBack) { for (int i = 1; i < 10; i++) { DropDownList1.Items.Add(i.ToString()); } } } protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e) { EmployeesPager emp = new EmployeesPager(); GridView1.DataSource = emp.GetEmployees((Convert.ToInt32(DropDownList1.SelectedItem.Text)-1),3); GridView1.DataBind(); }
最後更新：2017-04-02 03:42:39