WPF用流的方式上传/显示/下载图片文件(保存在数据库)

前两天有同事问我怎么将图片存入数据库,即兴写了个列子.

1.在数据库中,图片字段用varbinary(MAX)类型.

程序代码(下附完整的例子下载):

  1 using System;
  2  using System.Linq;
  3  using System.Windows;
  4  using System.Windows.Media.Imaging;
  5 using System.IO;
  6 using System.Data.Linq;
  7 
  8 namespace WpfUploadDispalyIMG
  9 {
 10 
 11     public partial class MainWindow : Window
 12     {
 13         DataClasses1DataContext db = new DataClasses1DataContext();
 14         public MainWindow()
 15         {
 16             InitializeComponent();
 17         }    
 18 
 19         private void btBrowse_Click(object sender, RoutedEventArgs e)
 20         {
 21             //创建＂打开文件＂对话框
 22             Microsoft.Win32.OpenFileDialog dlg = new Microsoft.Win32.OpenFileDialog();
 23 
 24             //设置文件类型过滤
 25             dlg.Filter = "图片|*.jpg;*.png;*.gif;*.bmp;*.jpeg";
 26 
 27             // 调用ShowDialog方法显示＂打开文件＂对话框
 28             Nullable<bool> result = dlg.ShowDialog();
 29             
 30             if (result == true)
 31             {
 32                 //获取所选文件名并在FileNameTextBox中显示完整路径
 33                 string filename = dlg.FileName;
 34                 FileNameTextBox.Text = filename;
 35 
 36                 //在image1中预览所选图片
 37                 BitmapImage image = new BitmapImage(new Uri(filename));
 38                 image1.Source = image;
 39                 image1.Width = image.Width;
 40                 image1.Height = image.Height;
 41             }
 42         }
 43       
 44         private void btUpdate_Click(object sender, RoutedEventArgs e)
 45         {
 46             if (!string.IsNullOrEmpty(FileNameTextBox.Text))
 47             {
 48                  UploadIMG();
 49                 MessageBox.Show("OK!");
 50                 FileNameTextBox.Text = string.Empty;
 51               
 52             }
 53             else
 54                 MessageBox.Show("请选择图片！");
 55         }
 56 
 57 
 58         //上传图片至数据库
 59         private void UploadIMG()
 60         {
 61             //将所选文件的读入字节数组img
 62             byte[] img = File.ReadAllBytes(FileNameTextBox.Text);
 63             string fileName = System.IO.Path.GetFileNameWithoutExtension(FileNameTextBox.Text);
 64                 //FileNameTextBox.Text.Substring(FileNameTextBox.Text.LastIndexOf('\\')+1);
 65             Crew newCrew = new Crew()
 66             {
 67                 photo = img,//将图片写入数据库
 68                 name = fileName
 69             };
 70             db.Crew.InsertOnSubmit(newCrew);
 71             db.SubmitChanges();
 72         }
 73 
 74         private void btShow_Click(object sender, RoutedEventArgs e)
 75         {
 76             try
 77             {
 78                 //根据文件名读取二进制形式的图片
 79                 Binary p = db.Crew.FirstOrDefault(c => c.name == tbName.Text.Trim()).photo;
 80                 byte[] img = p.ToArray();
 81                 ShowSelectedIMG(img);
 82             }
 83             catch (Exception ex)
 84             {
 85                 MessageBox.Show(ex.Message);
 86             }
 87         }
 88         //显示图片
 89         private void ShowSelectedIMG(byte[] img)
 90         {
 91             BitmapImage image = new BitmapImage();
 92             //以流的形式初始化图片
 93             image.BeginInit();
 94             image.StreamSource = new MemoryStream(img);
 95             image.EndInit();
 96 
 97             image1.Source = image;
 98             image1.Width = image.PixelWidth;
 99             image1.Height = image.PixelHeight;
100         }
101         //保存为文件
102         private void btSave_Click(object sender, RoutedEventArgs e)
103         {
104             //创建＂保存文件＂对话框
105           
106             Microsoft.Win32.SaveFileDialog dlg = new Microsoft.Win32.SaveFileDialog();
107             //设置默认文件类型
108             dlg.DefaultExt = ".png";
109             Nullable<bool> result = dlg.ShowDialog();
110 
111             if (result == true)
112             {
113                 //获取要保存文件名的完整路径
114                 string filename = dlg.FileName;
115                 //将文件流写入文件
116                 FileStream write = new FileStream(filename, FileMode.OpenOrCreate, FileAccess.ReadWrite, System.IO.FileShare.Read);
117                 Binary p = db.Crew.FirstOrDefault(c => c.name == tbName.Text.Trim()).photo;
118                 byte[] img = p.ToArray();
119                 write.Write(img, 0, img.Count());
120                write.Close();
121                MessageBox.Show("成功保存");
122             }
123         }
124     }
125 }

例子下载地址: https://files.cnblogs.com/Laro/WpfUploadDispalyIMG.rar

posted @ 2011-05-23 08:45  Laro  阅读(8933)  评论(2)  编辑  收藏  举报