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您好我正在尝试从数据库中获取字节数组并将其转换为可用于在我的 .aspx 页面中显示来自数据库的图像的东西。我正在使用严格的 c#。

这是我的代码。

SqlCommand picCommand = connection.CreateCommand();
picCommand.CommandText = ("SELECT ItemImage FROM Inventory WHERE ItemName = '" +         DropDownList1.SelectedItem.Text + "';");
connection.Open();

object returnPic; 
returnPic = picCommand.ExecuteScalar();//value that is read as the byte array or intended to be read as byte array.


    connection.Close();


    UTF8Encoding utf8 = new UTF8Encoding();
    //where i intend to convert the 
    byte[] image = utf8.GetBytes(returnPic.ToString()); 


    System.Drawing.Image myImage;

    using (MemoryStream inStream = new MemoryStream())
    {
        inStream.Write(image, 0, image.Length);

        myImage = Bitmap.FromStream(inStream);
    }




    this.ItemImageBox.Equals(myImage);

代码编译并运行，但是当它执行 myImage = Bitmap.FromStream(instream) 行时，我收到此错误 System.ArgumentException: Parameter is not valid。我实际上是通过查看各种不同的来源获得了这段代码，所以也许这里有人可以告诉我我是否做错了什么。

提前谢谢！

4

2 回答 2

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你可以尝试这样的事情，它应该适合你

public static Image LoadImage(byte[] imageBytes)
{
     Image image = null;
     using (var inStream = new MemoryStream(imageBytes))
     {
        image = Image.FromStream(ms);
     }
     return image;
}
于 2012-11-14T18:16:57.457 回答
0

这是我必须将字节数组转换为位图的扩展方法在此示例中，我使用将数据保存到 Sql Server 2008R2 数据库

    protected void btnParent1Upload_Click(object sender, EventArgs e)
    {
        ScriptManager.GetCurrent(this).RegisterPostBackControl(this.btnParent1Upload);
        FileUpload FileUpload1 = file_ImageParent1;
        string virtualFolder = "~/UpImages/";
        string physicalFolder = Server.MapPath(virtualFolder);
        FileUpload1.SaveAs(physicalFolder + FileUpload1.FileName);
        lbl_ResultParent1.Text = "Your file " + FileUpload1.FileName + " has been uploaded.";
        Parent1Pic.Visible = true;
        Parent1Pic.ImageUrl = virtualFolder + FileUpload1.FileName;
        byte[] imageBytes = PopulateImageBytes(physicalFolder + FileUpload1.FileName);
        ParentsInfo.Parent1Pic = imageBytes;
        imageBytes = null;
        FileUpload1 = null;
    }

    private static byte[] PopulateImageBytes(string p)
    {
        byte[] imageBytes = File.ReadAllBytes(p);
        return imageBytes;
    }

我有 StudentPic 定义如下

public byte[] StudentPic { get; set; }

我的 SQL 参数之一定义如下

sqlcmd.Parameters.AddWithValue("@Picture", (object)StudentPic ?? noImage);

这应该可以帮助您了解执行此操作的不同方法之一

于 2012-11-14T18:59:00.353 回答