|
準(zhǔn)備工作，在庫Im_Test中建立一張表Im_Info，此表中有兩個(gè)字段，分別為Pr_Id （INT），Pr_Info (IMAGE)，用來存儲圖形編號及圖形信息。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，并初始化PR_INFO字段。其語法如下：
- INSERT INTO Im_Info VALUES (1 ，0xFFFFFFFF)
第二步往表中寫入圖形信息。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(jìn)制數(shù)據(jù)，可以通過C 、Java等工具獲得。
注意在寫入圖形信息前必須先將此數(shù)據(jù)庫的 'select into/bulkcopy' 屬性設(shè)置為 True ，其語法如下：
- use master
- exec sp_dboption Im_Test ,'select into/bulkcopy' ,True
C#讀取Image數(shù)據(jù)類型：
（1）控制臺應(yīng)用程序下演示插入圖片
- public void InsertIMG()
- {
-
- //將需要存儲的圖片讀取為數(shù)據(jù)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）控制臺應(yīng)用程序下讀出并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(gè)圖片的位流
- int ArraySize= MyData.GetUpperBound(0);//獲得數(shù)據(jù)庫中存儲的位流數(shù)組的維度上限，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");//查看硬盤上的文件
- }
- }
（3）Web下picshow.aspx頁將圖片讀取出來并寫入到瀏覽器上呈現(xiàn)
- 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頁面讀取并顯示圖片，而真正引用該圖片時(shí)如下示例
- <img src="picshow.aspx" width="500" height="300" />
（5）Winform下將圖片寫入到sql數(shù)據(jù)庫image類型字段中的方法和以上方法基本一致，僅區(qū)別于可以利用多個(gè)對話框來幫助選取存儲圖片等，各個(gè)屬性可以方便的利用上
（6）Winform下讀取圖片在picturebox控件中顯示出來
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);
- //用指定的數(shù)據(jù)流來創(chuàng)建一個(gè)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并寫入到物理位置，然后再行利用該圖片呈現(xiàn)
- 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添加圖片方法一
- //picbox.ImageLocation = myUrl;
- //picbox.Width = 800;
- //picbox.Height = 300;
-
-
-
- //為picbox添加圖片方法二
- 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();
- }
轉(zhuǎn)自：http://www.cnblogs.com/samcn/archive/2008/08/24/1275072.html
|
