如何使用c#从asp.net中的sql数据库中检索图像。
我想从数据库中检索图像文件,然后在标签中显示图像。
我尝试此代码,但无法正常工作
<asp:Image ID="Image1" runat="server" ImageUrl="" Height="150px" Width="165px" />
Byte[] bytes = (Byte[])ds.Tables[0].Rows[0]["image"]; Response.Buffer = true; Response.Charset = ""; Response.Cache.SetCacheability(HttpCacheability.NoCache); Response.ContentType = "image/jpg"; Response.BinaryWrite(bytes); Response.Flush(); Response.End();
如何赋予ImageUrl=""此图片的链接???
ImageUrl=""
创建generic http handler如下
generic http handler
using System; using System.Configuration; using System.Web; using System.IO; using System.Data; using System.Data.SqlClient; public class ShowImage : IHttpHandler { public void ProcessRequest(HttpContext context) { Int32 empno; if (context.Request.QueryString["id"] != null) empno = Convert.ToInt32(context.Request.QueryString["id"]); else throw new ArgumentException("No parameter specified"); context.Response.ContentType = "image/jpeg"; Stream strm = ShowEmpImage(empno); byte[] buffer = new byte[4096]; int byteSeq = strm.Read(buffer, 0, 4096); while (byteSeq > 0) { context.Response.OutputStream.Write(buffer, 0, byteSeq); byteSeq = strm.Read(buffer, 0, 4096); } //context.Response.BinaryWrite(buffer); } public Stream ShowEmpImage(int empno) { string conn = ConfigurationManager.ConnectionStrings["EmployeeConnString"].ConnectionString; SqlConnection connection = new SqlConnection(conn); string sql = "SELECT empimg FROM EmpDetails WHERE empid = @ID"; SqlCommand cmd = new SqlCommand(sql,connection); cmd.CommandType = CommandType.Text; cmd.Parameters.AddWithValue("@ID", empno); connection.Open(); object img = cmd.ExecuteScalar(); try { return new MemoryStream((byte[])img); } catch { return null; } finally { connection.Close(); } } public bool IsReusable { get { return false; } } }
并显示图像如下
Image1.ImageUrl = "~/ShowImage.ashx?id=" + id;
下面有一些链接 在数据库中的GridView中显示图像? 如何在Asp.net的图像控件中显示数据库中的图像? 使用C#http://www.dotnetcurry.com/ShowArticle.aspx? ID=129从ASP.net中的数据库显示图像