ASP.NET 上传图片至数据库并读取图片显示

aspx

          <asp:Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click" />

<td>
         <img id="imghead"  runat="server" src='../images/noimg.gif'>
</td>

<td>
         相关图片:
 </td>


<td>
                    <%-- <asp:FileUpload ID="FileUpload1" runat="server" onchange="previewImage(this)" ></asp:FileUpload>--%>
                        <asp:FileUpload ID="FileUpload1" runat="server" />
                        <%--<hr />
                        <asp:Label ID="LabMessage1" runat="server" ForeColor="red" /><br />
                        <asp:Label ID="LabMessage2" runat="server" />--%>
                    

</td>

　　

aspx.cs

public string _path = "";

protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                if (Request.QueryString["key"] != null)
                {
                    string sql = "select * from ChiH_Material where id=" + Request.QueryString["key"].ToString();
                    DataTable dt = bc.ReadTable(sql);
                    if (dt.Rows.Count > 0)
                    {
                        imghead.Src = dt.Rows[0]["picture"].ToString();

                    }

                }
                else
                {
                }
            }
        }

 

 protected void Button1_Click(object sender, EventArgs e)
        {
            try
            {
                   uploadfile2();

                    if (Request.QueryString["key"] != null)
                    {
                        string sql = "update ChiH_Material set inside_model='" + inside_model.Value.Trim() + "',model='" + model.Value.Trim() + "',high_flower='" + high_flower.Value.Trim() + "',breadth='" + breadth.Value.Trim() + "',Stock='" + Stock.Value.Trim() + "',go_code='" + go_code.Value.Trim() + "',product_price='" + product_price.Value.Trim() + "',Grey_price='" + Grey_price.Value.Trim() + "',remark='" + remark.Value.Trim() + "',picture='" + _path + "' where id=" + Request.QueryString["key"].ToString();
                        bc.execsql(sql);

                    }
                    else
                    {
                        string sql = "insert into ChiH_Material(inside_model,sup_no,model,high_flower,breadth,Stock,go_code,product_price,Grey_price,remark,picture) values('" + inside_model.Value.Trim() + "','" + sup_no.Value.Trim() + "','" + model.Value.Trim() + "','" + high_flower.Value.Trim() + "','" + breadth.Value.Trim() + "','" + Stock.Value.Trim() + "','" + go_code.Value.Trim() + "','" + product_price.Value.Trim() + "','" + Grey_price.Value.Trim() + "','" + remark.Value.Trim() + "','" + _path + "')";
                        bc.execsql(sql);
                    }
                    Response.Write("<script type="text/javascript">alert('保存成功');window.returnValue='ok';window.close();</script>");
                               
            }
            catch (Exception)
            {
                Response.Write("<script type="text/javascript">alert('操作失败！');window.returnValue='ok';window.close();</script>");
            }
        }

 

 

public void uploadfile2() 
        {
            bool fileOK = false; 
            string path = Server.MapPath("../drawimg/");
            _path = "../drawimg/" + FileUpload1.FileName;
            if (FileUpload1.HasFile)
            {
                String fileExtension = System.IO.Path.GetExtension(FileUpload1.FileName).ToLower();
                String[] allowedExtensions = { ".gif", ".png", ".bmp", ".jpg" };
                for (int i = 0; i < allowedExtensions.Length; i++)
                {
                    if (fileExtension == allowedExtensions[i])
                    {
                        fileOK = true;
                    }
                }
            }
            if (fileOK)
            {
                try
                {
                    FileUpload1.SaveAs(path + FileUpload1.FileName);
                    
                    //LabMessage1.Text = "文件上传成功.";
                    //LabMessage2.Text = "<b>原文件路径：</b>" + FileUpload1.PostedFile.FileName + "<br />" +
                    //              "<b>文件大小：</b>" + FileUpload1.PostedFile.ContentLength + "字节<br />" +
                    //              "<b>文件类型：</b>" + FileUpload1.PostedFile.ContentType + "<br />";
                }
                catch (Exception ex)
                {
                    //LabMessage1.Text = "文件上传不成功.";
                }
            }
            else
            {
                //LabMessage1.Text = "只能够上传图片文件.";
            }
        }