Wednesday, August 10, 2011

图片的二进制数据库存储和显示

1.将图片以二进制存入数据库
2.读取二进制图片在页面显示
3.设置Image控件显示从数据库中读出的二进制图片
4.GridView中ImageField以URL方式显示图片
5.GridView显示读出的二进制图片
6.用ashx显示图片

1.将图片以二进制存入数据库

C#
--------------------------
//保存图片到数据库
protected void Button1_Click(object sender, EventArgs e)
{
//图片路径
string strPath = "~/photo/03.JPG";
string strPhotoPath = Server.MapPath(strPath);
//读取图片
FileStream fs = new System.IO.FileStream(strPhotoPath, FileMode.Open, FileAccess.Read);
BinaryReader br = new BinaryReader(fs);
byte[] photo = br.ReadBytes((int)fs.Length);
br.Close();
fs.Close();
//存入
SqlConnection myConn = new SqlConnection("Data Source=127.0.0.1;Initial Catalog=TestDB;User ID=sa;Password=sa");
string strComm = " INSERT INTO personPhoto(personName, personPhotoPath, personPhoto) ";
strComm += " VALUES('wangwu', '" + strPath + "', @photoBinary )";
SqlCommand myComm = new SqlCommand(strComm, myConn);
myComm.Parameters.Add("@photoBinary", SqlDbType.Binary,photo.Length);
myComm.Parameters["@photoBinary"].Value = photo;
myConn.Open();
myComm.ExecuteNonQuery();
myConn.Close();
}
2.读取二进制图片在页面显示

C#
--------------------------
//读取图片
SqlConnection myConn = new SqlConnection("Data Source=127.0.0.1;Initial Catalog=TestDB;User ID=sa;Password=sa");
string strComm = " SELECT personPhoto FROM personPhoto WHERE personName='wangwu' ";
SqlCommand myComm = new SqlCommand(strComm, myConn);
myConn.Open();
SqlDataReader dr = myComm.ExecuteReader();
while (dr.Read())
{
byte[] photo = (byte[])dr["personPhoto"];
this.Response.BinaryWrite(photo);
}
dr.Close();
myConn.Close();



SqlConnection myConn = new SqlConnection("Data Source=127.0.0.1;Initial Catalog=TestDB;User ID=sa;Password=sa");
SqlDataAdapter myda = new SqlDataAdapter(" SELECT personPhoto FROM personPhoto WHERE personName='wangwu' ", myConn);
DataSet myds = new DataSet();
myConn.Open();
myda.Fill(myds);
myConn.Close();
//
byte[] photo = (byte[])myds.Tables[0].Rows[0]["personPhoto"];
this.Response.BinaryWrite(photo);

3.设置Image控件显示从数据库中读出的二进制图片

C#
---------------------------------------------
SqlConnection myConn = new SqlConnection("Data Source=192.168.0.36;Initial Catalog=TestDB;User ID=sa;Password=sa");
SqlDataAdapter myda = new SqlDataAdapter(" SELECT personPhoto FROM personPhoto WHERE personName='wangwu' ", myConn);
DataSet myds = new DataSet();
myConn.Open();
myda.Fill(myds);
myConn.Close();
//
byte[] photo = (byte[])myds.Tables[0].Rows[0]["personPhoto"];
//图片路径
string strPath = "~/photo/wangwu.JPG";
string strPhotoPath = Server.MapPath(strPath);
//保存图片文件
BinaryWriter bw = new BinaryWriter(File.Open(strPhotoPath,FileMode.OpenOrCreate));
bw.Write(photo);
bw.Close();
//显示图片
this.Image1.ImageUrl = strPath

4.GridView中ImageField以URL方式显示图片
----------------------------







后台直接绑定即可

5.GridView显示读出的二进制图片
------------------------------
//样板列













//绑定

C#
protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
if (e.Row.RowIndex < 0) return; // System.ComponentModel.Container string strPersonName = (string)DataBinder.Eval(e.Row.DataItem, "personName"); Image tmp_Image = (Image)e.Row.Cells[2].FindControl("Image1"); if (!System.Convert.IsDBNull(DataBinder.Eval(e.Row.DataItem, "personPhoto"))) { // byte[] photo = (byte[])DataBinder.Eval(e.Row.DataItem, "personPhoto"); //图片路径 string strPath = "~/photo/" + strPersonName.Trim() + ".JPG"; string strPhotoPath = Server.MapPath(strPath); //保存图片文件 BinaryWriter bw = new BinaryWriter(File.Open(strPhotoPath, FileMode.OpenOrCreate)); bw.Write(photo); bw.Close(); //显示图片 tmp_Image.ImageUrl = strPath; } } 6.用ashx显示调用图片 (1)aspx页面代码














(2).GetImage.ashx代码

<%@ WebHandler Language="C#" Class="GetImage" %>

using System;
using System.Web;
using System.IO;
using System.Drawing;
using System.Data.SqlClient;

public class GetImage : IHttpHandler {

public void ProcessRequest (HttpContext context) {
//context.Response.ContentType = "text/plain";
//context.Response.Write("Hello World");
string id = (string)context.Request["id"];

MemoryStream stream = new MemoryStream();
SqlConnection conn = new SqlConnection(@"server=.;database=DBNAME;uid=sa;pwd=sa");
Bitmap bm = null;
Image image = null;
try
{
conn.Open();
SqlCommand cmd = new SqlCommand("select photo from table2 where id='" + id + "'", conn);
byte[] blob = (byte[])cmd.ExecuteScalar();

context.Response.ContentType = "image/gif";
context.Response.BinaryWrite(blob);
context.Response.End();

#region
/*
stream.Write(blob, 78, blob.Length - 78);
bm = new Bitmap(stream);

int width = 48;
int height = (int)(width * ((double)bm.Height / (double)bm.Width));


// getthumbnailimage生成缩略图
image = bm.GetThumbnailImage(width, height, null, IntPtr.Zero);

context.Response.ContentType= "image/jpeg";

image.Save(context.Response.OutputStream,System.Drawing.Imaging.ImageFormat.Jpeg);
*/
#endregion
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
finally
{
if (image != null)
image.Dispose();
if (bm != null)
bm.Dispose();
stream.Close();
conn.Close();

}

}

public bool IsReusable {
get {
return false;
}
}


}

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