Silverlight学习笔记六(Silverlight 2.0/3.0/4.0图片上传)

上一篇做了个本地图片浏览的功能，这次找到图片上传的代码，记录一下。
添加一个“一般处理程序”Handler.ashx

<%@ WebHandler Language="C#" Class="Handler" %>

using System;
using System.Web;

using System.IO;

public class Handler : IHttpHandler
{

    public void ProcessRequest(HttpContext context)
    {
        //获取上传的数据流
        Stream sr = context.Request.InputStream;
        try
        {
            //生成随机的文件名（本DEMO中的上传图片名称也可用参数方法传递过来）
            string chars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
            Random rnd = new Random();
            string filename = "";
            for (int i = 1; i <= 32; i++)
            {
                filename += chars.Substring(rnd.Next(chars.Length), 1);
            }

            byte[] buffer = new byte[4096];
            int bytesRead = 0;
            //将当前数据流写入服务器端文件夹ClientBin下
            using (FileStream fs = File.Create(context.Server.MapPath("ClientBin/" + filename + ".jpg"), 4096))
            {
                while ((bytesRead = sr.Read(buffer, 0, buffer.Length)) > 0)
                {
                    //向文件中写信息
                    fs.Write(buffer, 0, bytesRead);
                }
            }

            context.Response.ContentType = "text/plain";
            context.Response.Write("Hello World");
        }
        catch (Exception e)
        {
            context.Response.ContentType = "text/plain";
            context.Response.Write("上传失败, 错误信息:" + e.Message);
        }
        finally
        {
            sr.Dispose();
        }
    }

    public bool IsReusable
    {
        get
        {
            return false;
        }
    }

}

 

新建一个silverlight用户控件UploadPic.xaml

<UserControl x:Class="SilverlightXML.UploadPic"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    Width="400" Height="300">
    <Grid x:Name="LayoutRoot" Background="Black" ShowGridLines="False" Margin="8">
        <Grid.ColumnDefinitions>
        <ColumnDefinition Width="196" />
        <ColumnDefinition Width="*" />
        </Grid.ColumnDefinitions>
        <Grid.RowDefinitions>
        <RowDefinition Height="*" />
        <RowDefinition Height="48" />
        </Grid.RowDefinitions>
        <ListBox x:Name="myList" HorizontalAlignment="Stretch" VerticalAlignment="Stretch"
            ItemsSource="{Binding}"
            Grid.Row="0"
            Grid.Column="0"
            Grid.RowSpan="2"
            SelectionChanged="OnSelectionChanged" >
            <ListBox.ItemTemplate>
            <DataTemplate>
            <TextBlock Text="{Binding Name}" />
            </DataTemplate>
            </ListBox.ItemTemplate>
        </ListBox>
    <!--<my:GridSplitter Width="1" HorizontalAlignment="Left" VerticalAlignment="Stretch" Grid.Column="1"></my:GridSplitter>-->

        <Image x:Name="myImage" Grid.Column="1" />
        <StackPanel Grid.Row="1" Background="white" Grid.ColumnSpan="2" Orientation="Horizontal" HorizontalAlignment="Stretch">
        <Button Grid.Row="1"
        Grid.Column="0"
        Content="选择图片"
        Margin="8" Click="OnClick" FontSize="16" Width="100"/>
        <Button Grid.Row="1"
        Grid.Column="2"
        Content="上传该图片"
        Margin="8" Click="OnUpLoadClick" FontSize="16" Width="100"/>
        </StackPanel> 
    </Grid>

</UserControl>

 

UploadPic.xaml.cs

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.Windows.Browser;
using System.IO;
using System.Windows.Media.Imaging;

namespace SilverlightXML
{
    public partial class UploadPic : UserControl
    {
        public UploadPic()
        {
            InitializeComponent();
        }
        void OnClick(object sender, EventArgs args)
        {
            OpenFileDialog openFileDialog = new OpenFileDialog()
            {
                Filter = "Jpeg Files (*.jpg)|*.jpg|All Files(*.*)|*.*",
                Multiselect = true
            };

            if (openFileDialog.ShowDialog() == true)//.DialogResult.OK)
            {
                myList.DataContext = openFileDialog.Files;
            }
        }

        void OnUpLoadClick(object sender, EventArgs args)
        {
            if (fi != null)
            {
                WebClient webclient = new WebClient();

                webclient.OpenWriteCompleted += new OpenWriteCompletedEventHandler(webclient_OpenWriteCompleted);
                webclient.OpenWriteAsync(new Uri("http://localhost:51262/SilverlightXMLSite/Handler.ashx", UriKind.Absolute), "POST", fi.OpenRead());
            }
            else
            {
                HtmlPage.Window.Alert("请选取相应图片!!!");
            }
        }

        void webclient_OpenWriteCompleted(object sender, OpenWriteCompletedEventArgs e)
        {
            //将图片数据流发送到服务器上
            Stream inputStream = e.UserState as Stream;
            Stream outputStream = e.Result;

            byte[] buffer = new byte[4096];
            int bytesRead = 0;

            while ((bytesRead = inputStream.Read(buffer, 0, buffer.Length)) > 0)
            {
                outputStream.Write(buffer, 0, bytesRead);
            }
            outputStream.Close();
            inputStream.Close(); 
            HtmlPage.Window.Alert("图片上传成功!!!");
        }


        FileInfo fi; //获取选定图片信息//silverlight 2.0中是FileDialogFileInfo

        private void OnSelectionChanged(object sender, SelectionChangedEventArgs e)
        {
            if ((e.AddedItems != null) && (e.AddedItems.Count > 0))
            {
                fi = e.AddedItems[0] as FileInfo;

                if (fi != null)
                {
                    using (Stream stream = fi.OpenRead())
                    {
                        BitmapImage image = new BitmapImage();
                        image.SetSource(stream);
                        myImage.Source = image;
                        myImage.Visibility = Visibility.Visible;
                        stream.Close();
                    }
                }
            }
        }

    }

}

估计不能上传大文件，有专门的开源项目，有空找找。