C# 图像裁剪无法正常工作

代码片段应该裁剪图像，但是裁剪的大小是正确的，但是裁剪从左上角开始。这些图像更清楚、更准确地说明了问题

/// <summary>
/// Handles the Click event of the UploadButton control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
/// <remarks></remarks>
protected void UploadButton_Click(object sender, EventArgs e)
{

    String path = HttpContext.Current.Request.PhysicalApplicationPath + "images\\";


    Boolean FileOK = false;
    Boolean FileSaved = false;

    if (Upload.HasFile)
    {
        Session["WorkingImage"] = Upload.FileName;

        String FileExtension = Path.GetExtension(Session["WorkingImage"].ToString()).ToLower();

        String[] allowedExtensions = { ".png", ".jpeg", ".jpg", ".gif" };

        for (int i = 0; i < allowedExtensions.Length; i++)
        {
            if (FileExtension == allowedExtensions[i])
            {
                FileOK = true;
            }
        }
    }


    if (FileOK)
    {
        try
        {
            Upload.PostedFile.SaveAs(path + Session["WorkingImage"]);
            FileSaved = true;
        }

        catch (Exception ex)
        {
            ErrorLabel.Text = "File could not be uploaded." + ex.Message;
            ErrorLabel.Visible = true;
            FileSaved = false;
        }
    }

    else
    {
        ErrorLabel.Text = "Cannot accept files of this type.";
        ErrorLabel.Visible = true;
    }


    if (FileSaved)
    {
        UploadPanel.Visible = false;
        CropPanel.Visible = true;
        CropImage.ImageUrl = "~/Images/" + Session["WorkingImage"];
    }
}

/// <summary>
/// Handles the Click event of the CropButton control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
/// <remarks></remarks>
protected void CropButton_Click(object sender, EventArgs e)
{
    String path = HttpContext.Current.Request.PhysicalApplicationPath + "Images\\";

    string ImageName = Session["WorkingImage"].ToString();
    int w = Convert.ToInt32(Convert.ToDouble(W.Value));
    int h = Convert.ToInt32(Convert.ToDouble(H.Value));
    int x = Convert.ToInt32(Convert.ToDouble(X.Value));
    int y = Convert.ToInt32(Convert.ToDouble(Y.Value));


    byte[] CropImage = Crop(path + ImageName, w, h, x, y);

    using (MemoryStream ms = new MemoryStream(CropImage, 0, CropImage.Length))
    {
        ms.Write(CropImage, 0, CropImage.Length);

        using (Image CroppedImage = Image.FromStream(ms, true))
        {
            string SaveTo = path + "crop" + ImageName;
            CroppedImage.Save(SaveTo, CroppedImage.RawFormat);
            CropPanel.Visible = false;
            CroppedPanel.Visible = true;
            this.CroppedImage.ImageUrl = "~/Images/crop" + ImageName;
        }
    }
}

#endregion

#region Methods

/// <summary>
/// Crops the specified image.
/// </summary>
/// <param name="image">The image.</param>
/// <param name="width">The width.</param>
/// <param name="height">The height.</param>
/// <param name="x">The x value.</param>
/// <param name="y">The y value.</param>
/// <returns></returns>
/// <remarks></remarks>
private static byte[] Crop(string image, int width, int height, int x, int y)
{
    try
    {
        using (Image OriginalImage = Image.FromFile(image))
        {
            using (Bitmap bmp = new Bitmap(width, height))
            {
                //bmp.SetResolution(OriginalImage.HorizontalResolution, OriginalImage.VerticalResolution);

                using (Graphics Graphic = Graphics.FromImage(bmp))
                {
                    Graphic.SmoothingMode = SmoothingMode.AntiAlias;
                    Graphic.InterpolationMode = InterpolationMode.HighQualityBicubic;
                    Graphic.PixelOffsetMode = PixelOffsetMode.HighQuality;
                    //Graphic.DrawImage(OriginalImage, new Rectangle(0, 0, width, height), x, -y, width, height,GraphicsUnit.Pixel);
                    Graphic.DrawImage(OriginalImage, new Rectangle(0, 0, width, height), x, y, width, height, GraphicsUnit.Pixel);
                    MemoryStream ms = new MemoryStream();
                    bmp.Save(ms, OriginalImage.RawFormat);

                    return ms.GetBuffer();
                }
            }
        }
    }
    catch (Exception e)
    {
        throw e;
    }
}

坐标约为：x=68，y=28，宽度=176，高度=174。下面是裁剪代码

/// <summary>
/// Handles the Click event of the UploadButton control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
/// <remarks></remarks>
protected void UploadButton_Click(object sender, EventArgs e)
{

    String path = HttpContext.Current.Request.PhysicalApplicationPath + "images\\";


    Boolean FileOK = false;
    Boolean FileSaved = false;

    if (Upload.HasFile)
    {
        Session["WorkingImage"] = Upload.FileName;

        String FileExtension = Path.GetExtension(Session["WorkingImage"].ToString()).ToLower();

        String[] allowedExtensions = { ".png", ".jpeg", ".jpg", ".gif" };

        for (int i = 0; i < allowedExtensions.Length; i++)
        {
            if (FileExtension == allowedExtensions[i])
            {
                FileOK = true;
            }
        }
    }


    if (FileOK)
    {
        try
        {
            Upload.PostedFile.SaveAs(path + Session["WorkingImage"]);
            FileSaved = true;
        }

        catch (Exception ex)
        {
            ErrorLabel.Text = "File could not be uploaded." + ex.Message;
            ErrorLabel.Visible = true;
            FileSaved = false;
        }
    }

    else
    {
        ErrorLabel.Text = "Cannot accept files of this type.";
        ErrorLabel.Visible = true;
    }


    if (FileSaved)
    {
        UploadPanel.Visible = false;
        CropPanel.Visible = true;
        CropImage.ImageUrl = "~/Images/" + Session["WorkingImage"];
    }
}

/// <summary>
/// Handles the Click event of the CropButton control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
/// <remarks></remarks>
protected void CropButton_Click(object sender, EventArgs e)
{
    String path = HttpContext.Current.Request.PhysicalApplicationPath + "Images\\";

    string ImageName = Session["WorkingImage"].ToString();
    int w = Convert.ToInt32(Convert.ToDouble(W.Value));
    int h = Convert.ToInt32(Convert.ToDouble(H.Value));
    int x = Convert.ToInt32(Convert.ToDouble(X.Value));
    int y = Convert.ToInt32(Convert.ToDouble(Y.Value));


    byte[] CropImage = Crop(path + ImageName, w, h, x, y);

    using (MemoryStream ms = new MemoryStream(CropImage, 0, CropImage.Length))
    {
        ms.Write(CropImage, 0, CropImage.Length);

        using (Image CroppedImage = Image.FromStream(ms, true))
        {
            string SaveTo = path + "crop" + ImageName;
            CroppedImage.Save(SaveTo, CroppedImage.RawFormat);
            CropPanel.Visible = false;
            CroppedPanel.Visible = true;
            this.CroppedImage.ImageUrl = "~/Images/crop" + ImageName;
        }
    }
}

#endregion

#region Methods

/// <summary>
/// Crops the specified image.
/// </summary>
/// <param name="image">The image.</param>
/// <param name="width">The width.</param>
/// <param name="height">The height.</param>
/// <param name="x">The x value.</param>
/// <param name="y">The y value.</param>
/// <returns></returns>
/// <remarks></remarks>
private static byte[] Crop(string image, int width, int height, int x, int y)
{
    try
    {
        using (Image OriginalImage = Image.FromFile(image))
        {
            using (Bitmap bmp = new Bitmap(width, height))
            {
                //bmp.SetResolution(OriginalImage.HorizontalResolution, OriginalImage.VerticalResolution);

                using (Graphics Graphic = Graphics.FromImage(bmp))
                {
                    Graphic.SmoothingMode = SmoothingMode.AntiAlias;
                    Graphic.InterpolationMode = InterpolationMode.HighQualityBicubic;
                    Graphic.PixelOffsetMode = PixelOffsetMode.HighQuality;
                    //Graphic.DrawImage(OriginalImage, new Rectangle(0, 0, width, height), x, -y, width, height,GraphicsUnit.Pixel);
                    Graphic.DrawImage(OriginalImage, new Rectangle(0, 0, width, height), x, y, width, height, GraphicsUnit.Pixel);
                    MemoryStream ms = new MemoryStream();
                    bmp.Save(ms, OriginalImage.RawFormat);

                    return ms.GetBuffer();
                }
            }
        }
    }
    catch (Exception e)
    {
        throw e;
    }
}

//
///处理UploadButton控件的单击事件。
/// 
///事件的来源。
///包含事件数据的实例。
/// 
受保护的无效上载按钮\u单击（对象发送者，事件参数e）
{
字符串路径=HttpContext.Current.Request.PhysicalApplicationPath+“images\\”；
布尔FileOK=false；
布尔FileSaved=false；
if（Upload.HasFile）
{
会话[“WorkingImage”]=Upload.FileName；
String FileExtension=Path.GetExtension（会话[“WorkingImage”].ToString（））.ToLower（）；
字符串[]allowedExtensions={.png“，.jpeg“，.jpg“，.gif”}；
for（int i=0；i

裁剪看起来不像是从左上角开始的，就在左上角附近。在我看来，

x

和

y

坐标是错误的。我建议您手动插入自己的

x

和

y

值，直到获得所需的图像，然后找出

x

和

y

值与预期值不同的原因

/// <summary>
/// Handles the Click event of the UploadButton control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
/// <remarks></remarks>
protected void UploadButton_Click(object sender, EventArgs e)
{

    String path = HttpContext.Current.Request.PhysicalApplicationPath + "images\\";


    Boolean FileOK = false;
    Boolean FileSaved = false;

    if (Upload.HasFile)
    {
        Session["WorkingImage"] = Upload.FileName;

        String FileExtension = Path.GetExtension(Session["WorkingImage"].ToString()).ToLower();

        String[] allowedExtensions = { ".png", ".jpeg", ".jpg", ".gif" };

        for (int i = 0; i < allowedExtensions.Length; i++)
        {
            if (FileExtension == allowedExtensions[i])
            {
                FileOK = true;
            }
        }
    }


    if (FileOK)
    {
        try
        {
            Upload.PostedFile.SaveAs(path + Session["WorkingImage"]);
            FileSaved = true;
        }

        catch (Exception ex)
        {
            ErrorLabel.Text = "File could not be uploaded." + ex.Message;
            ErrorLabel.Visible = true;
            FileSaved = false;
        }
    }

    else
    {
        ErrorLabel.Text = "Cannot accept files of this type.";
        ErrorLabel.Visible = true;
    }


    if (FileSaved)
    {
        UploadPanel.Visible = false;
        CropPanel.Visible = true;
        CropImage.ImageUrl = "~/Images/" + Session["WorkingImage"];
    }
}

/// <summary>
/// Handles the Click event of the CropButton control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
/// <remarks></remarks>
protected void CropButton_Click(object sender, EventArgs e)
{
    String path = HttpContext.Current.Request.PhysicalApplicationPath + "Images\\";

    string ImageName = Session["WorkingImage"].ToString();
    int w = Convert.ToInt32(Convert.ToDouble(W.Value));
    int h = Convert.ToInt32(Convert.ToDouble(H.Value));
    int x = Convert.ToInt32(Convert.ToDouble(X.Value));
    int y = Convert.ToInt32(Convert.ToDouble(Y.Value));


    byte[] CropImage = Crop(path + ImageName, w, h, x, y);

    using (MemoryStream ms = new MemoryStream(CropImage, 0, CropImage.Length))
    {
        ms.Write(CropImage, 0, CropImage.Length);

        using (Image CroppedImage = Image.FromStream(ms, true))
        {
            string SaveTo = path + "crop" + ImageName;
            CroppedImage.Save(SaveTo, CroppedImage.RawFormat);
            CropPanel.Visible = false;
            CroppedPanel.Visible = true;
            this.CroppedImage.ImageUrl = "~/Images/crop" + ImageName;
        }
    }
}

#endregion

#region Methods

/// <summary>
/// Crops the specified image.
/// </summary>
/// <param name="image">The image.</param>
/// <param name="width">The width.</param>
/// <param name="height">The height.</param>
/// <param name="x">The x value.</param>
/// <param name="y">The y value.</param>
/// <returns></returns>
/// <remarks></remarks>
private static byte[] Crop(string image, int width, int height, int x, int y)
{
    try
    {
        using (Image OriginalImage = Image.FromFile(image))
        {
            using (Bitmap bmp = new Bitmap(width, height))
            {
                //bmp.SetResolution(OriginalImage.HorizontalResolution, OriginalImage.VerticalResolution);

                using (Graphics Graphic = Graphics.FromImage(bmp))
                {
                    Graphic.SmoothingMode = SmoothingMode.AntiAlias;
                    Graphic.InterpolationMode = InterpolationMode.HighQualityBicubic;
                    Graphic.PixelOffsetMode = PixelOffsetMode.HighQuality;
                    //Graphic.DrawImage(OriginalImage, new Rectangle(0, 0, width, height), x, -y, width, height,GraphicsUnit.Pixel);
                    Graphic.DrawImage(OriginalImage, new Rectangle(0, 0, width, height), x, y, width, height, GraphicsUnit.Pixel);
                    MemoryStream ms = new MemoryStream();
                    bmp.Save(ms, OriginalImage.RawFormat);

                    return ms.GetBuffer();
                }
            }
        }
    }
    catch (Exception e)
    {
        throw e;
    }
}

---

我将它与我拥有的一些裁剪代码进行了比较（我知道这些代码是有效的），我看不出您实际的

Crop

方法有任何问题。

只是一个注释：捕获异常只是重新抛出它是绝对没有意义的。让事情变得更糟

抛出e

将实际替换原始调用堆栈。@BrianRasmussen true，虽然说实话，我复制并粘贴了，对此并不担心，但感谢您注意到它。很好的观察，我发现它确实不是从左上角开始的。结果显示的图像设置为200*200px，当它的实际尺寸可能更大时。JCrop从img元素中获取命令，但c#代码作用于实际图像。因此，我必须计算img元素与实际图像的比率，然后补偿JCrop值。i、 e.存在各种各样的缩放问题。

/// <summary>
/// Handles the Click event of the UploadButton control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
/// <remarks></remarks>
protected void UploadButton_Click(object sender, EventArgs e)
{

    String path = HttpContext.Current.Request.PhysicalApplicationPath + "images\\";


    Boolean FileOK = false;
    Boolean FileSaved = false;

    if (Upload.HasFile)
    {
        Session["WorkingImage"] = Upload.FileName;

        String FileExtension = Path.GetExtension(Session["WorkingImage"].ToString()).ToLower();

        String[] allowedExtensions = { ".png", ".jpeg", ".jpg", ".gif" };

        for (int i = 0; i < allowedExtensions.Length; i++)
        {
            if (FileExtension == allowedExtensions[i])
            {
                FileOK = true;
            }
        }
    }


    if (FileOK)
    {
        try
        {
            Upload.PostedFile.SaveAs(path + Session["WorkingImage"]);
            FileSaved = true;
        }

        catch (Exception ex)
        {
            ErrorLabel.Text = "File could not be uploaded." + ex.Message;
            ErrorLabel.Visible = true;
            FileSaved = false;
        }
    }

    else
    {
        ErrorLabel.Text = "Cannot accept files of this type.";
        ErrorLabel.Visible = true;
    }


    if (FileSaved)
    {
        UploadPanel.Visible = false;
        CropPanel.Visible = true;
        CropImage.ImageUrl = "~/Images/" + Session["WorkingImage"];
    }
}

/// <summary>
/// Handles the Click event of the CropButton control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
/// <remarks></remarks>
protected void CropButton_Click(object sender, EventArgs e)
{
    String path = HttpContext.Current.Request.PhysicalApplicationPath + "Images\\";

    string ImageName = Session["WorkingImage"].ToString();
    int w = Convert.ToInt32(Convert.ToDouble(W.Value));
    int h = Convert.ToInt32(Convert.ToDouble(H.Value));
    int x = Convert.ToInt32(Convert.ToDouble(X.Value));
    int y = Convert.ToInt32(Convert.ToDouble(Y.Value));


    byte[] CropImage = Crop(path + ImageName, w, h, x, y);

    using (MemoryStream ms = new MemoryStream(CropImage, 0, CropImage.Length))
    {
        ms.Write(CropImage, 0, CropImage.Length);

        using (Image CroppedImage = Image.FromStream(ms, true))
        {
            string SaveTo = path + "crop" + ImageName;
            CroppedImage.Save(SaveTo, CroppedImage.RawFormat);
            CropPanel.Visible = false;
            CroppedPanel.Visible = true;
            this.CroppedImage.ImageUrl = "~/Images/crop" + ImageName;
        }
    }
}

#endregion

#region Methods

/// <summary>
/// Crops the specified image.
/// </summary>
/// <param name="image">The image.</param>
/// <param name="width">The width.</param>
/// <param name="height">The height.</param>
/// <param name="x">The x value.</param>
/// <param name="y">The y value.</param>
/// <returns></returns>
/// <remarks></remarks>
private static byte[] Crop(string image, int width, int height, int x, int y)
{
    try
    {
        using (Image OriginalImage = Image.FromFile(image))
        {
            using (Bitmap bmp = new Bitmap(width, height))
            {
                //bmp.SetResolution(OriginalImage.HorizontalResolution, OriginalImage.VerticalResolution);

                using (Graphics Graphic = Graphics.FromImage(bmp))
                {
                    Graphic.SmoothingMode = SmoothingMode.AntiAlias;
                    Graphic.InterpolationMode = InterpolationMode.HighQualityBicubic;
                    Graphic.PixelOffsetMode = PixelOffsetMode.HighQuality;
                    //Graphic.DrawImage(OriginalImage, new Rectangle(0, 0, width, height), x, -y, width, height,GraphicsUnit.Pixel);
                    Graphic.DrawImage(OriginalImage, new Rectangle(0, 0, width, height), x, y, width, height, GraphicsUnit.Pixel);
                    MemoryStream ms = new MemoryStream();
                    bmp.Save(ms, OriginalImage.RawFormat);

                    return ms.GetBuffer();
                }
            }
        }
    }
    catch (Exception e)
    {
        throw e;
    }
}