Save the asp.net image to the database, read the image from the database, and display it

This article summarizes two questions about saving images in asp.net to the database, reading images from the database, and displaying program code.

Example 1

The Code is as follows:

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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; // Read the image into a byte array 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; // CREATE Command 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; // Create a 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 (); }

Read:

Reading images from databases to picturebox

The Code is as follows:

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SqlConnection conn = new SqlConnection (@ "data source = chenyuming2004VSdotNET; uid = sa; pwd = cym; database = lhf "); Conn. Open (); SqlCommand cmd = new SqlCommand ("select photo 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;

Example 2

How to save images to a database:

The Code is as follows:

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Public void imgToDB (string SQL) {// The imge variable name required to be saved in the parameter SQL is @ images // Call method such as 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 ();} }

Read the image in the database and display it in picturebox:

Method 1:

The Code is as follows:

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Private void ShowImage (string SQL) { // Call method such as 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 (); }

Method 2: select a row in dg:

The Code is as follows:

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Private void dg_MouseUp (object sender, MouseEventArgs e) { // Select the entire row If (e. Button = System. Windows. Forms. MouseButtons. Left) {// User ID, name, gender, ID card number, nationality, school, department, campus, department, phone number, photo // Display the photo 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 ("An error occurred while reading photos from the database! "); } } Else PictureBox1.Image = null; } }