Asp.Net上传文件到Access数据中,并从数据库中读取文件并保存

首先在Access中建立一个表结构为:
表名:img

字段名 字段类型 说明
ID 自动编号 系统分配ID值
Imgtype 文本 上传文件类型
imgdata OLE对象 上传文件数据

aspx 页面主要代码

<form id="form1" runat="server">
<div>
<asp:FileUpload ID="FileUpload1" runat="server" Width="345px" />
<asp:Button ID="Button1" runat="server"
Text="上传到数据库" onclick="Button1_Click" />
<asp:Button ID="Button2" runat="server" Text="读取数据库到文件"
onclick="Button2_Click" /><asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
</div>
</form>

Cs文件代码

System.Data.OleDb.OleDbConnection conn = new System.Data.OleDb.OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Password=;User ID=admin;Data Source=D:\\WEB\\MyVs2008\\MyVs2008\\App_Data\\supervod.mdb");
protected void Button1_Click(object sender, EventArgs e)
{
if (!IsValid) return;
if (FileUpload1.PostedFile.FileName != "")
{
int datalength = this.FileUpload1.PostedFile.ContentLength; //获取上传文件大小
byte[] databuffer = new byte[datalength]; //建立文件字节数组,缓存空间
System.IO.Stream objstream = this.FileUpload1.PostedFile.InputStream;
objstream.Read(databuffer, 0, datalength);
string ext = System.IO.Path.GetExtension(FileUpload1.PostedFile.FileName);
System.Data.OleDb.OleDbCommand cmd = new System.Data.OleDb.OleDbCommand();
cmd.Connection = conn;
cmd.CommandText = "insert into img(imgtype,imgdata) values(@imgtype,@imgdata)";
cmd.Parameters.Add(new System.Data.OleDb.OleDbParameter("@imgtype", System.Data.OleDb.OleDbType.VarChar)).Value = ext;
cmd.Parameters.Add(new System.Data.OleDb.OleDbParameter("@imgdata", System.Data.OleDb.OleDbType.Binary)).Value = databuffer;
conn.Open();
cmd.ExecuteNonQuery();
conn.Close();
}
}

protected void Button2_Click(object sender, EventArgs e)
{
System.Data.OleDb.OleDbDataReader dr = null;
System.Data.OleDb.OleDbCommand cmd = new System.Data.OleDb.OleDbCommand();
byte[] FileData=null;
string type="";
cmd.CommandText = "select imgdata,imgtype from img where id=@ID";
cmd.Parameters.Add(new System.Data.OleDb.OleDbParameter("@ID", System.Data.OleDb.OleDbType.Integer)).Value = TextBox1.Text.Trim();
cmd.Connection = conn;
conn.Open();
dr = cmd.ExecuteReader();
if (dr.Read())
{
FileData = (byte[])dr["imgdata"];
type=dr["imgtype"].ToString();
}
dr.Close();
conn.Close();
System.IO.FileStream fs = new System.IO.FileStream("d:\\aaa" + type, System.IO.FileMode.Create);
System.IO.BinaryWriter bw = new System.IO.BinaryWriter(fs);
bw.Write(FileData, 0, FileData.Length);
bw.Close();
}

代码很简单,这里只做了一个演示,保存文件名为固定名称,其实可以在数据库里加入一个文件名了字段,这样就可以解决