抛出 IO 异常（进程无法访问文件“文件名”，因为它正被另一个进程使用

Question

抛出 IO 异常（进程无法访问文件 'filename'，因为它正被某个...

我无法从我的服务器路径中删除图像文件它给出了进程无法访问文件“FileName”的错误，因为它正被另一个进程使用。我尝试了很多方法，但仍然徒劳无功。请帮我解决这个问题。

这是我的代码片段。

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;

//============主块=================

watermark();
DeleteImages(); 

              \\ Here is My Delete Method That I Call To Delete The Images

//===== ==== 我的删除文件的删除方法==================

            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);
                 }

             }

\ ==== 在另一张图像上制作水印的方法声明。=======

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

不要只加载图像 - 文档确实说文件或流必须在 Image 实例的持续时间内可用。 相反，从文件中加载它，从中创建一个新图像，然后处理原始图像：

Image imgPhoto = GetCopyImage(Server.MapPath(".\TmpImages\SavedImage.jpg"));
... 


private Image GetCopyImage(string path)
    {
    using (Image im = Image.FromFile(path))
        {
        Bitmap bm = new Bitmap(im);
        return bm;
        }
    }

如果您只是加载它，那么图像引用将保持文件打开直到它被释放 - 这可能不会在应用程序关闭之前发生。