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MVVM模式下WPF動態(tài)綁定展示圖片

更新時間：2017年06月30日 11:57:12 作者：Jugg書生

這篇文章主要為大家詳細介紹了MVVM模式下WPF動態(tài)綁定展示圖片的相關(guān)資料，具有一定的參考價值，感興趣的小伙伴們可以參考一下

MVVM模式下WPF動態(tài)展示圖片，界面選擇圖標，復(fù)制到項目中固定目錄下面，保存到數(shù)據(jù)庫的是相對路徑，再次讀取的時候是根據(jù)數(shù)據(jù)庫的相對路徑去獲取項目中絕對路徑的圖片展示。

首先在ViewModel中

//屬性定義
    BitmapImage _ImageSource;
    /// <summary>
    /// 顯示的圖標
    /// </summary>
    public BitmapImage ImageSource
    {
      get { return _ImageSource; }
      set
      {
        _ImageSource = value;
        NotifyOfPropertyChange("ImageSource");
      }
    }

    string _ImagePath;
    /// <summary>
    /// 顯示的圖標路徑
    /// </summary>
    public string ImagePath
    {
      get { return _ImagePath; }
      set
      {
        _ImagePath = value;
        NotifyOfPropertyChange("ImagePath");
      }
    }

//初始化數(shù)據(jù)
//編輯的時候綁定數(shù)據(jù)
public GroupInfoViewModel(sys_Right_Group groupInfo, OperType type)
    {
      if (type == OperType.Edit || type == OperType.Show)
      {
        IsAdd = false;
        TitleName = "編輯分組";
        RightGroup = groupInfo;
        ImagePath = groupInfo.ImagePath; 
        GetImgData(groupInfo.ImagePath);
      }
    }
    /// <summary>
    /// 獲取圖片數(shù)據(jù)
    /// </summary>
    /// <param name="imgPath">相對路徑</param>
    private void GetImgData(string imgPath)
    {
      if (string.IsNullOrEmpty(imgPath)) return;
      try
      {
        
        string fileName = System.Environment.CurrentDirectory + imgPath; //獲取文件的絕對路徑
        byte[] buf;
        if (!PathToByte(fileName, out buf))
        {
          MessageHelper.ShowAutoCloseWarning("獲取圖標失敗");
          return;
        }
        ImageSource =ByteToImage(buf);
      }
      catch (Exception ex)
      {
        throw ex;
      }
    }

//界面選擇圖片按鈕事件
   /// <summary>
    /// 修改圖片
    /// </summary>
    public void ChangedIcon()
    {
      try
      {
        OpenFileDialog open = new OpenFileDialog();
        open.Filter = string.Format("照片|*.jpg;*.jpeg;*.png;*.gif;*.bmp");
        if (open.ShowDialog() == true)
        {
          var path = open.FileName;
          //檢查圖標目錄，絕對路徑下面
          string NewPath = System.Environment.CurrentDirectory + @"\Images\Tile\Group\";
          string newFile = NewPath + Path.GetFileName(path);
          if (!System.IO.Directory.Exists(NewPath))
          {
            System.IO.Directory.CreateDirectory(NewPath);
          }
          File.Copy(path, newFile, true); //復(fù)制文件到目錄絕對路徑文件夾
          FileInfo info = new FileInfo(newFile); //新文件
          if (info.Length > MenuViewModel.UserImageMaxLength)
          {
            MessageHelper.ShowAutoCloseWarning(string.Format("圖標不能大于{0}M",
              MenuViewModel.UserImageMaxLength / 1024 / 1024));
            return;
          }
          byte[] buf;
          if (!PathToByte(path, out buf))
          {
            MessageHelper.ShowAutoCloseWarning("修改失敗");
            return;
          }
          ImageSource = ByteToImage(buf);
          ImagePath = @"\Images\Tile\Group\" + Path.GetFileName(path); //顯示相對路徑

        }
      }
      catch (Exception ex)
      {

        throw ex;
      }
    }

點擊保存的時候再把相對路徑保存到數(shù)據(jù)庫RightGroup.ImagePath = ImagePath;

//公共幫助方法

//把圖片文件轉(zhuǎn)換為byte數(shù)組
 public static bool PathToByte(string path, out byte[] buffer)
    {
      FileStream fs = new FileStream(path, FileMode.Open, FileAccess.Read);
      try
      {
        buffer = new byte[fs.Length];
        fs.Read(buffer, 0, (int)fs.Length);
        return true;
      }
      catch (Exception ex)
      {
        buffer = null;
        return false;
      }
      finally
      {
        if (fs != null)
        {
          //關(guān)閉資源  
          fs.Close();
        }
      }
      
    }

//把byte數(shù)組轉(zhuǎn)化為BitmapImage 
    public static BitmapImage ByteToImage(byte[] buf)
    {
      BitmapImage bmp = new BitmapImage();
      bmp.BeginInit();
      bmp.StreamSource = new MemoryStream(buf);
      bmp.EndInit();

      return bmp;
    }

View 界面綁定代碼：

<Button Grid.Row="0" Grid.Column="0" Content="選擇圖片" cm:Message.Attach="[Click]=[ChangedIcon()]" Style="{StaticResource BtnOperationStyle}" Height="20" Width="70"></Button>
          <Grid Grid.Row="0" Grid.Column="1" Background="LightGray">
            <Image Height="120" Width="150" Stretch="Fill" Source="{Binding ImageSource,Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"></Image>
    </Grid>
   <Label Grid.Row="1" Grid.Column="0" Style="{StaticResource GridColumnLabelStyle}" Content="路徑："></Label>
<TextBox Grid.Row="1" Grid.Column="1" Style="{StaticResource StyleForTextBox}" Text="{Binding ImagePath,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" Height="30" TextAlignment="Center" IsReadOnly="True"></TextBox>

界面效果：