ASP.NET下如何上传图片到数据库，并且读出图片

来源：互联网发布：js insertrow align 编辑：程序博客网时间：2024/05/15 00:48

答1：首先在SQL Server中建立一个图片存储的数库表，ImageData Column为图象二进制数据储存字段，ImageContentType Column为图象文件类型记录字段，ImageDescription Column为储蓄图象文件说明字段,ImageSize Column为储存图象文件长度字段，结构如下： CREATE TABLE [dbo].[ImageStore] ( [ImageID] [int] IDENTITY (1, 1) NOT NULL , [ImageData] [image] NULL , [ImageContentType] [varchar] (50) COLLATE Chinese_PRC_CI_AS NULL , [ImageDescription] [varchar] (200) COLLATE Chinese_PRC_CI_AS NULL , [ImageSize] [int] NULL ) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY] */ //UpLoadImage.aspx程序内容如下： <%@ Page Inherits="UploadImage.UploadImage" SRC="UpLoadImage.cs" Language="C#"%> <HTML><title>上传图片</title> <BODY bgcolor="#FFFFFF"> <FORM ENCTYPE="multipart/form-data" RUNAT="server" ID="Form1"> <TABLE RUNAT="server" WIDTH="700" ALIGN="left" ID="Table1" cellpadding="0" cellspacing="0" border="0"> <TR> <TD>上传图片(选择你要上传的图片)</TD> <TD> <INPUT TYPE="file" ID="UP_FILE" RUNAT="server" STYLE="Width:320" ACCEPT="text/*" NAME="UP_FILE"> </TD> </TR> <TR> <TD> 文件说明(添加上传图片说明，如：作者、出处) </TD> <TD> <asp:TextBox RUNAT="server" WIDTH="239" ID="txtDescription" MAINTAINSTATE="false" /> </TD> </TR> <TR> <TD> <asp:Label RUNAT="server" ID="txtMessage" FORECOLOR="red" MAINTAINSTATE="false" /> </TD> <TD> <asp:Button RUNAT="server" WIDTH="239" ONCLICK="Button_Submit" TEXT="Upload Image" /> </TD> </TR> </TABLE> </FORM> </BODY> </HTML> //------------------------------------------------------------------- //UpLoadImage.cs程序内容如下： using System; using System.Web; using System.IO; using System.Data; using System.Data.SqlClient; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.HtmlControls; namespace UploadImage { public class UploadImage : Page { protected HtmlInputFile UP_FILE; //HtmlControl、WebControls控件对象 protected TextBox txtDescription; protected Label txtMessage; protected Int32 FileLength = 0; //记录文件长度变量 protected void Button_Submit(System.Object sender, System.EventArgs e) { HttpPostedFile UpFile = UP_FILE.PostedFile; //HttpPostedFile对象，用于读取图象文件属性 FileLength = UpFile.ContentLength; //记录文件长度 try { if (FileLength == 0) { //文件长度为零时 txtMessage.Text = "<b>请你选择你要上传的文件</b>"; } else { Byte[] FileByteArray = new Byte[FileLength]; //图象文件临时储存Byte数组 Stream StreamObject = UpFile.InputStream; //建立数据流对像 //读取图象文件数据，FileByteArray为数据储存体，0为数据指针位置、FileLnegth为数据长度 StreamObject.Read(FileByteArray,0,FileLength); //建立SQL Server链接 SqlConnection Con = new SqlConnection("Data Source=Localhost;Initial Catalog=testdb;User ID=sa;Pwd=;"); String SqlCmd = "INSERT INTO ImageStore (ImageData, ImageContentType, ImageDescription, ImageSize) VALUES (@Image, @ContentType, @ImageDescription, @ImageSize)"; SqlCommand CmdObj = new SqlCommand(SqlCmd, Con); CmdObj.Parameters.Add("@Image",SqlDbType.Binary, FileLength).Value = FileByteArray; CmdObj.Parameters.Add("@ContentType", SqlDbType.VarChar,50).Value = UpFile.ContentType; //记录文件类型 //把其它单表数据记录上传 CmdObj.Parameters.Add("@ImageDescription", SqlDbType.VarChar,200).Value = txtDescription.Text; //记录文件长度，读取时使用 CmdObj.Parameters.Add("@ImageSize", SqlDbType.BigInt,8).Value = UpFile.ContentLength; Con.Open(); CmdObj.ExecuteNonQuery(); Con.Close(); txtMessage.Text = "<p><b>OK!你已经成功上传你的图片</b>";//提示上传成功 } } catch (Exception ex) { txtMessage.Text = ex.Message.ToString(); }}}} //---------------------------------------------------------------------- //好了，图片已经上传到数据库，现在还要干什么呢？当然是在数据库中读取及显示在Web页中啦,请看以下程序: //ReadImage.aspx程序内容如下： /----------------------------------------------------------------------- <%@ Page Inherits="ReadImage.MainDisplay" SRC="ReadImage.cs"%> //---------------------------------------------------------------------- //ReadImage.cs程序内容如下： using System; using System.Data; using System.Data.SqlClient; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.HtmlControls; namespace ReadImage { public class MainDisplay : System.Web.UI.Page { public void Page_Load(System.Object sender, System.EventArgs e) { int ImgID = Convert.ToInt32(Request.QueryString["ImgID"]); //ImgID为图片ID //建立数据库链接 SqlConnection Con = new SqlConnection("Data Source=KING;Initial Catalog=testdb;User ID=sa;Pwd=;"); String SqlCmd = "SELECT * FROM ImageStore WHERE ImageID = @ImageID"; SqlCommand CmdObj = new SqlCommand(SqlCmd, Con); CmdObj.Parameters.Add("@ImageID", SqlDbType.Int).Value = ImgID; Con.Open(); SqlDataReader SqlReader = CmdObj.ExecuteReader(); SqlReader.Read(); Response.ContentType = (string)SqlReader["ImageContentType"];//设定输出文件类型 //输出图象文件二进制数制 Response.OutputStream.Write((byte[])SqlReader["ImageData"], 0, (int)SqlReader["ImageSize"]); Response.End(); Con.Close(); //很简单吧^_^ } } } //-------------------------------------------------------------------- //最后，我们当然要把它在Web页面显示出来啦 //ShowImage.hml <html> <body> 这个是从数据库读取出来的图象：<img src="ReadImage.aspx?ImgID=1"> <body> </html> //------------------------------------------------------------------ //最后，这程序当然还很多改进之处，希望大家多想想多编编一定可以写出更多的图象上传程序 //Good Luck，engine ______________________________________________________________________________________________ 答2： up ______________________________________________________________________________________________ 答3：把图像文件上传到数据库，并从数据库读出采用参数上传图片到数据库: using System; using System.Collections; using System.ComponentModel; using System.Data; using System.Data.SqlClient; using System.Drawing; using System.Web; using System.Web.SessionState; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.HtmlControls; using System.IO; namespace myUpLoad { /// <summary> /// img2sql 的摘要说明。 /// </summary> public class img2sql : System.Web.UI.Page { protected System.Web.UI.WebControls.TextBox imgTitleTextBox; protected System.Web.UI.HtmlControls.HtmlInputFile upLoadImg; protected System.Web.UI.WebControls.RequiredFieldValidator RequiredFieldValidator1; protected System.Web.UI.WebControls.Button Button1; protected SqlConnection myConnection; private void Page_Load(object sender, System.EventArgs e) { // 在此处放置用户代码以初始化页面 string conn="server=(local);database=test;uid=sa;pwd=ilovenm"; myConnection=new SqlConnection(conn); } #region Web Form Designer generated code override protected void OnInit(EventArgs e) { // // CODEGEN：该调用是 ASP.NET Web 窗体设计器所必需的。 // InitializeComponent(); base.OnInit(e); } /// <summary> /// 设计器支持所需的方法 - 不要使用代码编辑器修改 /// 此方法的内容。 /// </summary> private void InitializeComponent() { this.Button1.Click += new System.EventHandler(this.Button1_Click); this.Load += new System.EventHandler(this.Page_Load); } #endregion private void Button1_Click(object sender, System.Eve