IOException：ファイルロックにより画像を削除できない

Question

私のサーバーパスから画像ファイルを削除できません。プロセスが「FileName」ファイルにアクセスできないというエラーが表示されます。私は多くの方法を試しましたが、まだすべてが無駄でした。この問題で私を助けてください。

ここはマイコードスニペットです。

using System; 
using System.Data; 
using System.Web; 
using System.Data.SqlClient; 
using System.Web.UI; 

using System.Web.UI.HtmlControls; 
using System.Globalization; 
using System.Web.Security; 
using System.Text; 
using System.DirectoryServices; 
using System.Collections; 
using System.IO; 
using System.Drawing; 
using System.Drawing.Imaging; 
using System.Drawing.Drawing2D; 

//============ Main Block ================= 

     byte[] data = (byte[])ds.Tables[0].Rows[0][0]; 
     MemoryStream ms = new MemoryStream(data); 
     Image returnImage = Image.FromStream(ms); 

     returnImage.Save(Server.MapPath(".\\TmpImages\\SavedImage.jpg"), System.Drawing.Imaging.ImageFormat.Jpeg); 


     returnImage.Dispose();  \\ I Tried this Dispose Method To Unlock The File But Nothing Done. 

     ms.Close(); \\ I Tried The Memory Stream Close Method Also But Its Also Not Worked For Me. 

     watermark(); \\ Here is My Water Mark Method That Print Water Mark Image on My Saved Image (Image That is Converted From Byte Array) 


     DeleteImages();     \\ Here is My Delete Method That I Call To Delete The Images 



//===== ==== My Delete Method To Delete Files================== 

      public void DeleteImages() 

      { 

       try 
        { 

         File.Delete(Server.MapPath(".\\TmpImages\\WaterMark.jpg"));  \\This Image Deleted Fine. 
         File.Delete(Server.MapPath(".\\TmpImages\\SavedImage.jpg")); \\ Exception Thrown On Deleting of This Image. 
        } 

       catch (Exception ex) 
        { 
        LogManager.LogException(ex, "Error in Deleting Images."); 
        Master.ShowMessage(ex.Message, true); 
       } 

      } 



\\ ==== Method Declartion That Make Watermark of One Image On Another Image.======= 

public void watermark()    
{ 


    //create a image object containing the photograph to watermark 
    Image imgPhoto = Image.FromFile(Server.MapPath(".\\TmpImages\\SavedImage.jpg")); 
    int phWidth = imgPhoto.Width; 
    int phHeight = imgPhoto.Height; 

    //create a Bitmap the Size of the original photograph 
    Bitmap bmPhoto = new Bitmap(phWidth, phHeight, PixelFormat.Format24bppRgb); 

    bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution); 

    //load the Bitmap into a Graphics object 
    Graphics grPhoto = Graphics.FromImage(bmPhoto); 

    //create a image object containing the watermark 
    Image imgWatermark = new Bitmap(Server.MapPath(".\\TmpImages\\PrintasWatermark.jpg")); 
    int wmWidth = imgWatermark.Width; 
    int wmHeight = imgWatermark.Height; 

    //Set the rendering quality for this Graphics object 
    grPhoto.SmoothingMode = SmoothingMode.AntiAlias; 

    //Draws the photo Image object at original size to the graphics object. 
    grPhoto.DrawImage(
     imgPhoto,        // Photo Image object 
     new Rectangle(0, 0, phWidth, phHeight), // Rectangle structure 
     0,          // x-coordinate of the portion of the source image to draw. 
     0,          // y-coordinate of the portion of the source image to draw. 
     phWidth,        // Width of the portion of the source image to draw. 
     phHeight,        // Height of the portion of the source image to draw. 
     GraphicsUnit.Pixel);     // Units of measure 

    //------------------------------------------------------- 
    //to maximize the size of the Copyright message we will 
    //test multiple Font sizes to determine the largest posible 
    //font we can use for the width of the Photograph 
    //define an array of point sizes you would like to consider as possiblities 
    //------------------------------------------------------- 


    //Define the text layout by setting the text alignment to centered 
    StringFormat StrFormat = new StringFormat(); 
    StrFormat.Alignment = StringAlignment.Center; 

    //define a Brush which is semi trasparent black (Alpha set to 153) 
    SolidBrush semiTransBrush2 = new SolidBrush(Color.FromArgb(153, 0, 0, 0)); 



    //define a Brush which is semi trasparent white (Alpha set to 153) 
    SolidBrush semiTransBrush = new SolidBrush(Color.FromArgb(153, 255, 255, 255)); 



    //------------------------------------------------------------ 
    //Step #2 - Insert Watermark image 
    //------------------------------------------------------------ 

    //Create a Bitmap based on the previously modified photograph Bitmap 
    Bitmap bmWatermark = new Bitmap(bmPhoto); 
    bmWatermark.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution); 
    //Load this Bitmap into a new Graphic Object 
    Graphics grWatermark = Graphics.FromImage(bmWatermark); 

    //To achieve a transulcent watermark we will apply (2) color 
    //manipulations by defineing a ImageAttributes object and 
    //seting (2) of its properties. 
    ImageAttributes imageAttributes = new ImageAttributes(); 

    //The first step in manipulating the watermark image is to replace 
    //the background color with one that is trasparent (Alpha=0, R=0, G=0, B=0) 
    //to do this we will use a Colormap and use this to define a RemapTable 
    ColorMap colorMap = new ColorMap(); 

    //My watermark was defined with a background of 100% Green this will 
    //be the color we search for and replace with transparency 
    colorMap.OldColor = Color.FromArgb(255, 0, 255, 0); 
    colorMap.NewColor = Color.FromArgb(0, 0, 0, 0); 

    ColorMap[] remapTable = { colorMap }; 

    imageAttributes.SetRemapTable(remapTable, ColorAdjustType.Bitmap); 

    //The second color manipulation is used to change the opacity of the 
    //watermark. This is done by applying a 5x5 matrix that contains the 
    //coordinates for the RGBA space. By setting the 3rd row and 3rd column 
    //to 0.3f we achive a level of opacity 
    float[][] colorMatrixElements = { 
              new float[] {1.0f, 0.0f, 0.0f, 0.0f, 0.0f},  
              new float[] {0.0f, 1.0f, 0.0f, 0.0f, 0.0f},   
              new float[] {0.0f, 0.0f, 1.0f, 0.0f, 0.0f},   
              new float[] {0.0f, 0.0f, 0.0f, 0.3f, 0.0f},   
              new float[] {0.0f, 0.0f, 0.0f, 0.0f, 1.0f}}; 
    ColorMatrix wmColorMatrix = new ColorMatrix(colorMatrixElements); 

    imageAttributes.SetColorMatrix(wmColorMatrix, ColorMatrixFlag.Default, 
     ColorAdjustType.Bitmap); 

    //For this example we will place the watermark in the upper right 
    //hand corner of the photograph. offset down 10 pixels and to the 
    //left 10 pixles 

    int xPosOfWm = ((phWidth - wmWidth) - 10); 
    int yPosOfWm = 10; 

    grWatermark.DrawImage(imgWatermark, 
     new Rectangle(xPosOfWm, yPosOfWm, wmWidth, wmHeight), //Set the detination Position 
     0,     // x-coordinate of the portion of the source image to draw. 
     0,     // y-coordinate of the portion of the source image to draw. 
     wmWidth,   // Watermark Width 
     wmHeight,   // Watermark Height 
     GraphicsUnit.Pixel, // Unit of measurment 
     imageAttributes); //ImageAttributes Object 

    //Replace the original photgraphs bitmap with the new Bitmap 
    imgPhoto = bmWatermark; 
    grPhoto.Dispose(); 
    grWatermark.Dispose(); 
    //save new image to file system. 
    imgPhoto.Save(Server.MapPath(".\\TmpImages\\WaterMark.jpg"), ImageFormat.Jpeg); 

    imgPhoto.Dispose(); 

    imgWatermark.Dispose(); 
} 

Answer 1

imgPhoto = bmWatermark; 

まず、imgPhoto.Dispose（）を呼び出さなかったという問題があります。ファイルはファイナライザスレッドが実行されるまでロックされますが、それはしばらく時間がかかります。

このような間違いを避けるためにステートメントを使用してステートメントを使用してください。

Answer 2

使用Process MonitorMark RussinovichによるとBryce Cogswellと、ファイルをロックしているプロセスを見つけます。たぶんそれはあなたのウイルス対策か何か他のものです。

Answer 3

"使用する"構成を使用してください。コードで例外が発生した場合、ストリームとイメージは破棄されず、ファイルがロックされる可能性があります。

また、画像をウォーターマーク方式で再度開いた場合は、そこにも廃棄する必要があります。

Answer 4

私は同じ問題がありました。そこで、SysInternalsのProcess Monitorを使用して、私のウイルス対策ソフトウェアのような別のプロセスがロックしているかどうかを確認しました。これは本当に私の場合でしたが、リアルタイムバックアップサービスもファイルの競合になっていました。

この問題を回避するために、次の方法を使用してファイルを複数回削除しました。他のプロセスは通常、非常に短時間だけロックを保持します。

public class FileHelper 
{ 
    public static void Delete(string path) 
    { 
     int attempts = 0; 
     const int maxAttempts = 3; 

     do 
     { 
      try 
      { 
       attempts++; 
       File.Delete(path); 

       if (attempts > 1) Trace.TraceInformation("File delete succeeded"); 

       return; 
      } 
      catch (IOException) 
      { 
       Trace.TraceWarning("Could not access file for delete, attempt {0} of {1}", attempts, maxAttempts); 

       if (attempts >= maxAttempts) throw; 
      } 
     } 
     while (attempts < maxAttempts); 
    } 
}