asp.net图片保存到数据库和从数据库读取图片并显示

作者：袖梨 2022-06-25

例1

 代码如下 复制代码

private void button2_Click_1(object sender, System.EventArgs e)

{

string pathName;

if (this.openFileDialog1.ShowDialog()==System.Windows.Forms.DialogResult.OK)

{

pathName = this.openFileDialog1.FileName;

System.Drawing.Image img = System.Drawing.Image.FromFile(pathName);

this.pictureBox1.Image = img;

//将图像读入到字节数组

System.IO.FileStream fs = new System.IO.FileStream(pathName,System.IO.FileMode.Open,System.IO.FileAccess.Read);

byte[] buffByte = new byte[fs.Length];

fs.Read(buffByte,0,(int)fs.Length);

fs.Close();

fs = null;

//建立Command命令

string comm = @"Insert into table1(img,name) values(@img,@name)";

this.sqlCommand1 = new System.Data.SqlClient.SqlCommand ();

this.sqlCommand1.CommandType = System.Data.CommandType.Text ;

this.sqlCommand1.CommandText = comm;

this.sqlCommand1.Connection = this.sqlConnection1 ;

//创建Parameter

this.sqlCommand1.Parameters.Add("@img",System.Data.SqlDbType.Image);

this.sqlCommand1.Parameters[0].Value =buffByte;

this.sqlCommand1.Parameters.Add("@name",System.Data.SqlDbType.VarChar);

this.sqlCommand1.Parameters[1].Value =pathName.Substring(pathName.LastIndexOf("")+1);

try

{

this.sqlConnection1.Open();

this.sqlCommand1.ExecuteNonQuery();

this.sqlConnection1.Close();

}

catch(System.Exception ee)

{

MessageBox.Show(ee.Message );

}

buffByte = null;

this.FillListBox();

}


读取：

从数据库读图片到picturebox

 代码如下 复制代码


SqlConnection conn=new SqlConnection(@"data source=chenyuming2004VSdotNET;uid=sa;pwd=cym;database=lhf");

conn.Open();

SqlCommand cmd=new SqlCommand("select 照片 from fuser where password='1b'",conn);

SqlDataReader reader=cmd.ExecuteReader();

reader.Read();

MemoryStream buf=new MemoryStream((byte[])reader[0]);

Image image=Image.FromStream(buf,true);

pictureBox1.Image=image;

例2

图片保存到数据库的方法：

 代码如下 复制代码

        public void imgToDB(string sql)
        {   //参数sql中要求保存的imge变量名称为@images
            //调用方法如：imgToDB("update UserPhoto set Photo=@images where UserNo='" + temp + "'");
            FileStream fs = File.OpenRead(t_photo.Text);
            byte[] imageb = new byte[fs.Length];
            fs.Read(imageb, 0, imageb.Length);
            fs.Close();
            SqlCommand com3 = new SqlCommand (sql,con);
            com3.Parameters.Add("@images", SqlDbType.Image).Value = imageb;
            if (com3.Connection.State == ConnectionState.Closed)
                com3.Connection.Open();
            try
            {
                com3.ExecuteNonQuery();
            }
            catch
            { }
            finally
            { com3.Connection.Close(); }
        }

数据库中读出图片并显示在picturebox中：

方法一：

 代码如下 复制代码
private void ShowImage(string sql)
     {
     //调用方法如：ShowImage("select Photo from UserPhoto where UserNo='" + userno +"'");
     SqlCommand cmd = new SqlCommand(sql, conn);
     conn.Open();
     byte[] b= (byte[])cmd.ExecuteScalar();
     if (b.Length 〉 0)
     {
     MemoryStream stream = new MemoryStream(b, true);
     stream.Write(b, 0, b.Length);
     pictureBox1.Image = new Bitmap(stream);
     stream.Close();
     }
     conn.Close();
     }

方法二：当在dg中选中某行时：

 代码如下 复制代码
  private void dg_MouseUp(object sender, MouseEventArgs e)
        {
            //整行选择
            if (e.Button == System.Windows.Forms.MouseButtons.Left)
            {//用户编号，姓名，性别，身份证号，籍贯，学院，系所，校区，部门，电话，照片
                 //显示相片
                object imgobj=dg[10, dg.CurrentRow.Index].Value;
                if (imgobj != null && !Convert.IsDBNull(imgobj))
                {
                    byte[] imgb = (byte[])imgobj;
                    MemoryStream memStream = new MemoryStream(imgb);
                    try
                    {
                        Bitmap myimge = new Bitmap(memStream);
                        this.pictureBox1.Image = myimge;
                    }
                    catch
                    {
                        DB.msgbox("从数据库读取相片失败！");
                    }
                }
                else
                    pictureBox1.Image = null;
            }
        }

相关文章

精彩推荐