学步园

在本教程中，主要为大家讲述如何使用DataGrid来对后台数据库进行CURD操作。由于CURD操作是与数据库交互中最为常用的，因此掌握其使用方法就显得尤为必要。本教程将使用Linq to SQL Class + Silverlight-enabled WCF Service来实现这一过程。

准备工作

1）建立起测试项目

2）创建测试用数据库

细节详情请见强大的DataGrid组件[2]_数据交互之ADO.NET Entity Framework——Silverlight学习笔记[10]。

创建Linq to SQL 数据模型类

细节详情请见强大的DataGrid组件[3]_数据交互之Linq to SQL——Silverlight学习笔记[11]。

建立Silverlight-enabled WCF Service数据通信服务

建立的过程参见强大的DataGrid组件[3]_数据交互之Linq to SQL——Silverlight学习笔记[11]。然而，必须要将文件EmployeeInfoWCFService.svc.cs修改为如下所示：

using System;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.ServiceModel.Activation;
using System.Collections.Generic;
using System.Text;
using EmployeesContext;
using EmployeesEntities;

namespace datagridcurd
{
    [ServiceContract(Namespace = "")]
    [AspNetCompatibilityRequirements(RequirementsMode = AspNetCompatibilityRequirementsMode.Allowed)]
    public class EmployeeInfoWCFService
    {
        [OperationContract]
        public List<Employees> GetEmployees()
        {
            EmployeeModelDataContext db = new EmployeeModelDataContext();
            return db.Employees.ToList();
        }
        
        [OperationContract]
        public void Insert(Employees employee)
        {
            EmployeeModelDataContext db = new EmployeeModelDataContext();
            string employeename = employee.EmployeeName;
            int employeeage = employee.EmployeeAge;
            string strsql = "INSERT INTO Employee(EmployeeName,EmployeeAge) 
              VALUES('" + employeename + "'," + employeeage.ToString() + ")";
            db.ExecuteCommand(strsql);
        }

        [OperationContract]
        public void Update(List<Employees> employee)
        {
            EmployeeModelDataContext db = new EmployeeModelDataContext();
            employee.ForEach( x =>
            {
                int employeeid = x.EmployeeID;
                string employeename = x.EmployeeName;
                int employeeage = x.EmployeeAge;
                string strsql = "UPDATE Employee SET EmployeeName='" + employeename +
"',EmployeeAge=" + employeeage.ToString() + "WHERE EmployeeID=" + employeeid.ToString();
                db.ExecuteCommand(strsql);
            });
        }

        [OperationContract]
        public void Delete(Employees employee)
        {
            EmployeeModelDataContext db = new EmployeeModelDataContext();
            int employeeid = employee.EmployeeID;
            string strsql = "DELETE FROM Employee WHERE EmployeeID="+employeeid.ToString();
            db.ExecuteCommand(strsql);
        }

        // Add more operations here and mark them with [OperationContract]
    }
}

 

创建SilverlightClient界面及组件代码

MainPage.xaml文件代码：

<UserControl
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
    mc:Ignorable="d" xmlns:data="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Data"
x:Class="SilverlightClient.MainPage"
    d:DesignWidth="320" d:DesignHeight="240">
    <Grid x:Name="LayoutRoot" Background="White" Width="320" Height="240">
        <data:DataGrid x:Name="dgEmployee" Margin="8,8,8,48" Background="#FFCEDBE8"/>
        <Button x:Name="btnGetData" Height="30" HorizontalAlignment="Left" Margin="8,0,0,8"
VerticalAlignment="Bottom" Width="64" Content="GetData"/>
        <Button x:Name="btnInsert" Height="30" HorizontalAlignment="Left" Margin="88,0,0,8" 
VerticalAlignment="Bottom" Width="64" Content="Insert"/>
        <Button x:Name="btnSave" Height="30" HorizontalAlignment="Right" Margin="0,0,88,8" 
VerticalAlignment="Bottom" Width="64" Content="Save"/>
        <Button x:Name="btnDelete" Height="30" HorizontalAlignment="Right" Margin="0,0,8,8" 
VerticalAlignment="Bottom" Width="64" Content="Delete"/>
    </Grid>
</UserControl>

MainPage.xaml.cs文件代码：

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Data.Services.Client;//引入System.Data.Services.Client命名空间
using SilverlightClient.EmployeeWCFServiceReference;//引入数据服务所在命名空间
using System.Collections.ObjectModel;//引入ObservableCollection所在命名空间

namespace SilverlightClient
{
    public partial class MainPage : UserControl
    {
        List<Employees> BoundData = new List<Employees>();
        int rowCount = 0;
        bool isInsertOrUpdate = false;

        public MainPage()
        {
            InitializeComponent();
            this.btnGetData.Click += new RoutedEventHandler(btnGetData_Click);
            this.btnInsert.Click += new RoutedEventHandler(btnInsert_Click);
            this.btnSave.Click += new RoutedEventHandler(btnSave_Click);
            this.btnDelete.Click += new RoutedEventHandler(btnDelete_Click);
        }

        void btnDelete_Click(object sender, RoutedEventArgs e)
        {
            EmployeeInfoWCFServiceClient webClient = new EmployeeInfoWCFServiceClient();
            webClient.DeleteAsync(dgEmployee.SelectedItem as Employees);
            webClient.DeleteCompleted += 

new EventHandler<System.ComponentModel.AsyncCompletedEventArgs>(webClient_DeleteCompleted);
        }

        void webClient_DeleteCompleted(object sender, System.ComponentModel.AsyncCompletedEventArgs e)
        {
            ;
        }

        void btnSave_Click(object sender, RoutedEventArgs e)
        {
            if (isInsertOrUpdate)
            {
                EmployeeInfoWCFServiceClient webClient = new EmployeeInfoWCFServiceClient();
                webClient.InsertAsync(dgEmployee.SelectedItem as Employees);
                webClient.InsertCompleted += 

new EventHandler<System.ComponentModel.AsyncCompletedEventArgs>(webClient_InsertCompleted);
            }
            else
            {
                EmployeeInfoWCFServiceClient webClient = new EmployeeInfoWCFServiceClient();
                ObservableCollection<Employees> updatemodel = new ObservableCollection<Employees>();
                foreach (object o in dgEmployee.ItemsSource)
                {
                    updatemodel.Add(o as Employees); 
                }
                webClient.UpdateAsync(updatemodel);
                webClient.UpdateCompleted += 

new EventHandler<System.ComponentModel.AsyncCompletedEventArgs>(webClient_UpdateCompleted);
            }
        }

        void webClient_UpdateCompleted(object sender, System.ComponentModel.AsyncCompletedEventArgs e)
        {
            ;
        }
        
        void  webClient_InsertCompleted(object sender, System.ComponentModel.AsyncCompletedEventArgs e)
        {
             ;
        }
        
        void btnInsert_Click(object sender, RoutedEventArgs e)
        {
            Employees u = new Employees();
            BoundData.Insert(rowCount, u);
            dgEmployee.SelectedIndex = rowCount;
            dgEmployee.BeginEdit();
            dgEmployee.ItemsSource = BoundData;
            isInsertOrUpdate = true;
        }

        void btnGetData_Click(object sender, RoutedEventArgs e)
        {
            EmployeeInfoWCFServiceClient webClient = new EmployeeInfoWCFServiceClient();
            webClient.GetEmployeesAsync();//异步调用
            webClient.GetEmployeesCompleted += 

new EventHandler<GetEmployeesCompletedEventArgs>(webClient_GetEmployeesCompleted);
        }

        void webClient_GetEmployeesCompleted(object sender, GetEmployeesCompletedEventArgs e)
        {
            BoundData = e.Result.ToList();
            dgEmployee.ItemsSource = BoundData;
            rowCount = BoundData.Count;
        }

    }
}

最终效果图：

作者：Kinglee
文章出处：Kinglee’s Blog (http://www.cnblogs.com/Kinglee/)
版权声明：本文的版权归作者与博客园共有。转载时须注明本文的详细链接，否则作者将保留追究其法律责任。