在c＃.net应用程序中将图像从数据库检索到窗体表单时出错 [英] error in retrievng image from database to windows form in c# .net application

问题描述

调试下面的代码时出错了。错误是参数无效。请任何人建议解决方案





代码是

when debugging the below code i got an error. The error is parameter is not valid. Pls anyone suggest a solution


the code is

 cn.copen();
SqlDataAdapter adt = new SqlDataAdapter("select image from reg where studentid='" + cmbstdid.Text + "' ", cn.con);
DataSet ds1 = new DataSet();
adt.Fill(ds1);
cn.cclose();
if (ds1.Tables[0].Rows.Count > 0)
{

    byte[] imageData = (byte[])ds1.Tables[0].Rows[0]["image"];
    Image newImage;
    using (MemoryStream ms = new MemoryStream(imageData, 0, imageData.Length))
    {
        ms.Write(imageData, 0, imageData.Length);
        newImage = Image.FromStream(ms, true);
        //error is shown in the above line
    }
    pictureBox1.Image = newImage;
    pic = ds1.Tables[0].Rows[0]["image"].ToString();

}

已添加代码块[/编辑]

Code block added[/Edit]

推荐答案

您好，< br $>


你必须将 MemoryStream 的位置设置为 0 ：

Hi,

You have to set the position of the MemoryStream to 0:

ms.Write(imageData, 0, imageData.Length);
ms.Seek(0, SeekOrigin.Begin); // Add this line. The Seek method sets the position of the Stream to 0
newImage = Image.FromStream(ms, true);

如果你得到同样的错误，试试

If you get the same error, try

ms.Write(imageData, 0, imageData.Length);
ms.Seek(0, SeekOrigin.Begin);
newImage = Image.FromStream(ms);

如果再次出现同样的错误，请尝试

And if you get the same error again, try

ms.Write(imageData, 0, imageData.Length);
ms.Seek(0, SeekOrigin.Begin);
newImage = (Image)new Bitmap(ms);

根据您的评论，您只保存图像的文件名，而不是图像本身。要了解如何将图像存储到数据库中，请阅读以下文章：使用Strored过程和C＃.net 从SQL Server存储和检索图像[ ^ ]



希望这有帮助。

According to your comment, you only save the file name of the image, not the image itself. To learn how to store an image into a database, read this article: Storing and Retrieving Images from SQL Server Using Strored Procedures and C#.net[^]

Hope this helps.

您好，



使用以下代码。这完美无缺。

Hi,

Use the below code.This works perfectly.

if (ds1.Tables[0].Rows.Count > 0)
{
            {
if(ds1.Tables[0].Rows[0]!=DBNull.Value)
{

                byte[] imageData = (byte[])ds1.Tables[0].Rows[0]["image"]
}
MemoryStream ms=new MemoryStreamm(imageData);
 pictureBox1.Image = Image.FromStream(ms);
}
else
 pictureBox1.Image=null;
}
}

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