sqlserver資料庫的image欄位存入方法 ,讀取
阿新 • • 發佈:2018-12-30
存入方法
private void button1_Click(object sender, EventArgs e) { openFileImage.Filter = "*.jpg|*.JPG|*.gif|*.GIF|*.bmp|*.BMP"; if (openFileImage.ShowDialog() == DialogResult.OK) { try { this.pictureBox1.Image = Image.FromStream(this.openFileImage.OpenFile()); string strimg = openFileImage.FileName.ToString(); //獲取檔案對話方塊中選定的檔名的字串,包括檔案路徑 FileStream fs = new FileStream(strimg, FileMode.Open, FileAccess.Read); BinaryReader br = new BinaryReader(fs); imgBytesIn = br.ReadBytes((int)fs.Length); //fs.Length檔案流的長度,用位元組表示 //從當前流中將count個位元組讀入位元組陣列中 //開啟資料庫 SqlConnection con = new SqlConnection("server=192.168.1.164,1433;uid=sa;pwd=mas_lxw;database=Relocation_DT"); con.Open(); SqlCommand cmd = new SqlCommand("update gytd set
[email protected]", con); cmd.Parameters.Add("@Image", SqlDbType.Image); cmd.Parameters["@Image"].Value = imgBytesIn; cmd.ExecuteNonQuery(); con.Close(); MessageBox.Show("圖片上傳成功"); } catch { MessageBox.Show("您選擇的圖片不能被讀取或檔案型別不對!", "錯誤", MessageBoxButtons.OK, MessageBoxIcon.Warning); this.pictureBox1.Image = null; } } }
準備工作,在庫Im_Test中建立一張表Im_Info,此表中有兩個欄位,分別為Pr_Id (INT),Pr_Info (IMAGE),用來儲存圖形編號及圖形資訊。其語法如下: CREATE TEALE Im_Info ( Pr_Id INT NULL , Pr_Info IMAGE NULL ) 第一步: 往表中插入一條記錄,並初始化PR_INFO欄位。其語法如下: INSERT INTO Im_Info VALUES (1 ,0xFFFFFFFF) 第二步往表中寫入圖形資訊。其語法如下: DECLARE @@ptrval varbinary(16) SELECT @@ptrval = TEXTPTR(Pr_Info) FROM Im_Info WHERE Pr_Id = 1 WRITETEXT Im_Text.Im_Info @@ptrval 0x624fd543fd….. 其中0x624fd543fd….. 為圖形的十六進位制資料,可以通過C 、Java等工具獲得。 注意在寫入圖形資訊前必須先將此資料庫的 'select into/bulkcopy' 屬性設定為 True ,其語法如下: use master exec sp_dboption Im_Test ,'select into/bulkcopy' ,True C#讀取Image資料型別: (1)控制檯應用程式下演示插入圖片 public void InsertIMG() { //將需要儲存的圖片讀取為資料流 FileStream fs = new FileStream(@"E:\c.jpg", FileMode.Open,FileAccess.Read); Byte[] btye2 = new byte[fs.Length]; fs.Read(btye2 , 0, Convert.ToInt32(fs.Length)); fs.Close(); using (SqlConnection conn = new SqlConnection(sqlconnstr)) { conn.Open(); SqlCommand cmd = new SqlCommand(); cmd.Connection = conn; cmd.CommandText = "insert into T_Img(imgfile) values(@imgfile)"; SqlParameter par = new SqlParameter("@imgfile", SqlDbType.Image); par.Value = bt; cmd.Parameters.Add(par); int t=(int)(cmd.ExecuteNonQuery()); if (t > 0) { Console.WriteLine("插入成功"); } conn.Close(); } } (2)控制檯應用程式下讀出並生成圖片到物理位置 public void Read() { byte[] MyData = new byte[0]; using (SqlConnection conn = new SqlConnection(sqlconnstr)) { conn.Open(); SqlCommand cmd = new SqlCommand(); cmd.Connection = conn; cmd.CommandText = "select * from T_img"; SqlDataReader sdr = cmd.ExecuteReader(); sdr.Read(); MyData = (byte[])sdr["ImgFile"];//讀取第一個圖片的位流 int ArraySize= MyData.GetUpperBound(0);//獲得資料庫中儲存的位流陣列的維度上限,用作讀取流的上限 FileStream fs = new FileStream(@"c:\00.jpg", FileMode.OpenOrCreate, FileAccess.Write); fs.Write(MyData, 0, ArraySize); fs.Close(); //-- 寫入到c:\00.jpg。 conn.Close(); Console.WriteLine("讀取成功");//檢視硬碟上的檔案 } } (3)Web下picshow.aspx頁將圖片讀取出來並寫入到瀏覽器上呈現 public void Read() { byte[] MyData = new byte[0]; using (SqlConnection conn = new SqlConnection(sqlconnstr)) { conn.Open(); SqlCommand cmd = new SqlCommand(); cmd.Connection = conn; cmd.CommandText = "select * from T_img"; SqlDataReader sdr = cmd.ExecuteReader(); sdr.Read(); MyData = (byte[])sdr["ImgFile"]; Response.ContentType = "image/gif"; Response.BinaryWrite(MyData); conn.Close(); Response.Write("讀取成功"); } (4)在web中可以如上picshow.aspx頁面讀取並顯示圖片,而真正引用該圖片時如下示例 <img src="picshow.aspx" width="500" height="300" /> (5)Winform下將圖片寫入到sql資料庫image型別欄位中的方法和以上方法基本一致,僅區別於可以利用多個對話方塊來幫助選取儲存圖片等,各個屬性可以方便的利用上 (6)Winform下讀取圖片在picturebox控制元件中顯示出來 方法一:利用MemoryStream 和System.Drawing.Image public void Read() { byte[] MyData = new byte[0]; using (SqlConnection conn = new SqlConnection(sqlconnstr)) { conn.Open(); SqlCommand cmd = new SqlCommand(); cmd.Connection = conn; cmd.CommandText = "select * from T_img"; SqlDataReader sdr = cmd.ExecuteReader(); sdr.Read(); MyData = (byte[])sdr["ImgFile"]; MemoryStream mystream = new MemoryStream(MyData); //用指定的資料流來建立一個image圖片 System.Drawing.Image img = System.Drawing.Image.FromStream(mystream, true); System.Windows.Forms.PictureBox picbox = new PictureBox(); picbox.Image = img; picbox.Left = 30; picbox.Top = 80; picbox.Width = 800; picbox.Height = 500; this.Controls.Add(picbox); mystream.Close(); conn.Close(); } } 方法二:將流直接讀取成圖片並寫入到物理位置,然後再行利用該圖片呈現 void Read() { using (SqlConnection conn = new SqlConnection(sqlconnstr)) { conn.Open(); SqlCommand cmd = new SqlCommand(); cmd.Connection = conn; cmd.CommandText = "select * from T_img"; SqlDataReader sdr = cmd.ExecuteReader(); sdr.Read(); byte[] Image_img = (byte[])sdr["ImgFile"]; if (Image_img.Length == 0) { return; } int filelength = Image_img.Length; string imageName = "1.jpg"; string myUrl = Environment.CurrentDirectory + "\\" + imageName; FileStream fs = new FileStream(myUrl, FileMode.OpenOrCreate,FileAccess.Write); BinaryWriter BW = new BinaryWriter(fs); BW.BaseStream.Write(Image_img, 0, filelength); BW.Flush(); BW.Close(); System.Windows.Forms.PictureBox picbox = new PictureBox(); //為picbox新增圖片方法一 //picbox.ImageLocation = myUrl; //picbox.Width = 800; //picbox.Height = 300; //為picbox新增圖片方法二 Bitmap bitmap = new Bitmap(myUrl); picbox.Width = 100;//bitmap.Width; picbox.Height = 80;//bitmap.Height; picbox.Image = (Image)bitmap; picbox.SizeMode = System.Windows.Forms.PictureBoxSizeMode.StretchImage; picbox.Left = 20; picbox.Top = 30; this.Controls.Add(picbox); conn.Close(); } }