Question

我傳遞一個查詢字符串到我的通用處理程序的圖像轉換從數據庫。 我有我的設計頁面

 <asp:TemplateField> 
     <ItemTemplate> 
     <asp:Image ID="Image1" runat="server" ImageUrl='<%# ImageHandler.ashx?IMG_ID=Eval("Image_ID")+ &IMG_type_ID=Eval("Type_ID_FK") %>' /> 
      </ItemTemplate> 
     </asp:TemplateField> 

我有上的ImageUrl問題上的以下問題。

下面是我的主設計師代碼

<form id="form1" runat="server"> 
<div style="width: 960px; height: 100%; padding: 0; margin: 0; font-size: 0.875em; 
    line-height: 1.785em;"> 
    <div> 
     <asp:Panel ID="Panel1" runat="server"> 
      <h1> 
       Welcome To Blue Marine! Please login with your account</h1> 
      <br /> 
      <h2> 
       Login Area 
      </h2> 
      <div> 
       Username 
       <asp:TextBox ID="txt_username" runat="server" ControlToValidate=" txt_username"></asp:TextBox><span>*</span><asp:RequiredFieldValidator 
        ID="RequiredFieldValidator1" runat="server" ErrorMessage="Please Enter Valid Entry" 
        ControlToValidate="txt_username"></asp:RequiredFieldValidator> 
       <br /> 
       Password 
       <asp:TextBox ID="txt_password" runat="server"></asp:TextBox><span>*</span><asp:RequiredFieldValidator 
        ID="RequiredFieldValidator2" runat="server" ControlToValidate="txt_password" 
        ErrorMessage="Please Enter Valid Entry"></asp:RequiredFieldValidator> 
       <br /> 
       <div style="margin-left: 90px"> 
        <asp:Button ID="btn_Submit" runat="server" Text="Submit" OnClick="btn_Submit_Click" /> 
       </div> 
     </asp:Panel> 
    </div> 
    <div> 
     <asp:Panel ID="Panel2" runat="server" Visible="False"> 
      <div style="text-align: right"> 
       Hello! 
       <asp:Label ID="lb_username" runat="server" Text="Label"></asp:Label> 
       <br /> 
       <div> 
        <asp:LinkButton ID="Linkbtn_signout" runat="server" OnClick="Linkbtn_signout_Click">SignOut</asp:LinkButton> 
       </div> 
      </div> 
      <div style="text-align: left"> 
       <h1> 
        Image Upload Section</h1> 
       <p> 
        You can upload Images here One at a time Format Supported JPG,BMP,PNG 
        <br /> 
       </p> 
       &nbsp;<asp:TextBox ID="txtName" runat="server"></asp:TextBox> 
       <asp:FileUpload ID="FileUpload1" runat="server" /><br /> 
       <asp:SqlDataSource ID="SqlDataSource_ImageType" runat="server" ConnectionString="<%$ ConnectionStrings:db_string2 %>" 
        SelectCommand="SELECT [Type_ID_PK], [TypeName] FROM [ImageType]"></asp:SqlDataSource> 
       <br /> 
       Select Image Type&nbsp; 
       <asp:DropDownList ID="DropDownList1" runat="server" DataSourceID="SqlDataSource_ImageType" 
        DataTextField="Type_ID_PK" DataValueField="Type_ID_PK"> 
       </asp:DropDownList> 
       <span>*</span> 
       <asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server" ErrorMessage="Select Image Type" 
        ControlToValidate="DropDownList1"></asp:RequiredFieldValidator> 
       <br /> 
       <asp:Button ID="btnUpload" runat="server" OnClick="btnUpload_Click" Text="Upload" /><br /> 
       <br /> 
       <asp:Label ID="lblMessage" runat="server"></asp:Label><br /> 
       <br /> 
       <br /> 
       <div style="text-align: center; margin-left: 170px"> 
        <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" DataSourceID="SqlDataSource_DbImage" 
         EnableModelValidation="True" AllowPaging="True" AllowSorting="True" Width="566px" 
         DataKeyNames="Image_ID,Type_ID_FK"> 
         <Columns> 
          <asp:BoundField DataField="Image_ID" HeaderText="Image_ID" InsertVisible="False" 
           ReadOnly="True" SortExpression="Image_ID" /> 
          <asp:BoundField DataField="Type_ID_FK" HeaderText="Type_ID_FK" SortExpression="Type_ID_FK" 
           ReadOnly="True" /> 
          <asp:BoundField DataField="ImageName" HeaderText="ImageName" SortExpression="ImageName" /> 
          <asp:TemplateField> 
           <ItemTemplate> 
            <asp:Image ID="Image1" runat="server" ImageUrl='<%# ImageHandler.ashx?IMG_ID=Eval("Image_ID")+ &IMG_type_ID=Eval("Type_ID_FK") %>' /> 
           </ItemTemplate> 
          </asp:TemplateField> 
         </Columns> 
        </asp:GridView> 
       </div> 
       <asp:SqlDataSource ID="SqlDataSource_DbImage" runat="server" ConnectionString="<%$ ConnectionStrings:db_string2 %>" 
        SelectCommand="SELECT * FROM [Image_Link]"></asp:SqlDataSource> 
      </div> 
     </asp:Panel> 
    </div> 
</div> 
</form> 

我後面的代碼：

public partial class Admin : System.Web.UI.Page 
{ 
    protected void Page_Load(object sender, EventArgs e) 
    { 
     if (Session.Count > 0) 
     { 
      try 
      { 
       string id = Convert.ToString(Session["UserID"]); 
       if (id != "") 
       { 
        if (!IsPostBack) 
        { 
         Panel1.Visible = false; 
         Panel2.Visible = true; 
        } 
        else 
        { 
         Panel1.Visible = false; 
         Panel2.Visible = true; 
        } 
       } 
      } 
      catch (NullReferenceException n) 
      { 

      } 


     } 
     else 
     { 
      if (!IsPostBack) 
      { 
       Panel1.Visible = true; 
      } 
     } 
    } 

    protected void btn_Submit_Click(object sender, EventArgs e) 
    { 
     Session.Clear(); 
     bool result = Check_User_Login(txt_username.Text, txt_password.Text); 
     if (result == true) 
     { 
      Panel1.Visible = false; 
      Panel2.Visible = true; 
     } 
     else 
     { 
      Response.Write("<script>alert('Admin Account Does not exist!');</script>"); 
     } 





    } 


    public bool Check_User_Login(string para_name, string para_password) 
    { 
     string db_username, dp_password; 
     Web_Eng.DatabaseConection.comm = new SqlCommand("Select Top 1 a.Admin_ID From [Admin] a Order By a.Admin_ID Desc;", Web_Eng.DatabaseConection.connect()); 
     int id = (int)Web_Eng.DatabaseConection.comm.ExecuteScalar(); 
     for (int i = 1; i <= id; i++) 
     { 
      Web_Eng.DatabaseConection.comm.CommandText = "select a.Admin_Name,a.[Password] from [Admin] a where a.Admin_ID=" + i + ";"; 

      #region use to retrieve whole row from database 

      Web_Eng.DatabaseConection.entrieRow_Reader = Web_Eng.DatabaseConection.comm.ExecuteReader(); 
      while (Web_Eng.DatabaseConection.entrieRow_Reader.Read()) 
      { 

       db_username = Web_Eng.DatabaseConection.entrieRow_Reader["Admin_Name"].ToString(); 
       dp_password = Web_Eng.DatabaseConection.entrieRow_Reader["Password"].ToString(); 

       if (db_username == para_name && dp_password == para_password) 
       { 

        Session["UserID"] = i; 
        lb_username.Text = db_username; 
        Web_Eng.DatabaseConection.entrieRow_Reader.Close(); 
        return true; 

       } 

      } 
      Web_Eng.DatabaseConection.entrieRow_Reader.Close(); 


      #endregion 
     } 
     return false; 
    } 

    protected void Linkbtn_signout_Click(object sender, EventArgs e) 
    { 
     Session.Clear(); 
     Page.Response.Redirect("Index.aspx"); 
    } 

    protected void btnUpload_Click(object sender, EventArgs e) 
    { 
     string strImageName = txtName.Text.ToString(); 
     if (FileUpload1.PostedFile != null && FileUpload1.PostedFile.FileName != "") 
     { 
      byte[] imageSize = new byte[FileUpload1.PostedFile.ContentLength]; 
      HttpPostedFile uploadedImage = FileUpload1.PostedFile; 
      uploadedImage.InputStream.Read(imageSize, 0, (int)FileUpload1.PostedFile.ContentLength); 


      // Create SQL Command 
      int id=Convert.ToInt32(DropDownList1.SelectedItem.Value); 
      int result = AddImage_DB(strImageName, id, imageSize); 
      if (result > 0) 
       lblMessage.Text = "File Uploaded"; 
      GridView1.DataBind(); 
     } 
    } 



    public int AddImage_DB(string para_imagename, int para_typeID, byte[] para_image) 
    { 
     try 
     { 
      //DatabaseConection.cmd.con; 
      Web_Eng.DatabaseConection.cmd.Connection = Web_Eng.DatabaseConection.connect(); 
      Web_Eng.DatabaseConection.cmd = new SqlCommand("Insert_Image_Table", Web_Eng.DatabaseConection.connect()); 
      Web_Eng.DatabaseConection.cmd.CommandType = CommandType.StoredProcedure; 
      Web_Eng.DatabaseConection.cmd.Parameters.Add(new SqlParameter("@typeID", SqlDbType.Int)).Value = para_typeID; 
      Web_Eng.DatabaseConection.cmd.Parameters.Add(new SqlParameter("@ImageName", SqlDbType.NVarChar)).Value = para_imagename; 
      Web_Eng.DatabaseConection.cmd.Parameters.Add(new SqlParameter("@convertedImage", SqlDbType.Image, para_image.Length)).Value = para_image; 
      Web_Eng.DatabaseConection.cmd.ExecuteNonQuery(); 
      return 1; 
     } 
     catch (Exception er) 
     { 

      Response.Write("<script>alert('Error');</script>"); 
      return 0; 
     } 
    } 
} 

我的通用處理器

public class ImageHandler : IHttpHandler 
{ 

    public void ProcessRequest(HttpContext context) 
    { 

     // Create SQL Command 
     Web_Eng.DatabaseConection.comm = new SqlCommand("Select img.ImageName,img.CompleteImage from Image_Link img where img.Image_ID=@IMG_ID and img.Type_ID_FK=@IMG_type_ID;", Web_Eng.DatabaseConection.connect()); 
     Web_Eng.DatabaseConection.cmd.CommandType = System.Data.CommandType.Text; 

     // Img ID 
     SqlParameter ImageID = new SqlParameter("@IMG_ID", System.Data.SqlDbType.Int); 
     ImageID.Value = context.Request.QueryString["IMG_ID"]; 

     // iMG Type ID 
     SqlParameter Image_Type_ID = new SqlParameter("@IMG_type_ID", System.Data.SqlDbType.Int); 
     Image_Type_ID.Value = context.Request.QueryString["IMG_type_ID"]; 


     // Adding Parameters 
     Web_Eng.DatabaseConection.cmd.Parameters.Add(ImageID); 
     Web_Eng.DatabaseConection.cmd.Parameters.Add(Image_Type_ID); 

     SqlDataReader dReader = Web_Eng.DatabaseConection.cmd.ExecuteReader(); 
     dReader.Read(); 
     context.Response.BinaryWrite((byte[])dReader["CompleteImage"]); 
     dReader.Close(); 
    } 

    public bool IsReusable 
    { 
     get 
     { 
      return false; 
     } 
    } 
} 

不知道什麼，我順便查詢字符串做錯了我的手柄

由於提前

Answer 1

嘗試的語法如下：

<asp:Image ID="Image1" runat="server" ImageUrl='ImageHandler.ashx?IMG_ID=<%# Eval("Image_ID")+&IMG_type_ID=Eval("Type_ID_FK") %>' /> 

Answer 2

謝謝大家我已經解決我自己的問題我張貼誰可能有同樣的問題，其他人的回答會幫助他們

只需更換

<asp:Image ID="Image1" runat="server" ImageUrl='<%# ImageHandler.ashx?IMG_ID=Eval("Image_ID")+ &IMG_type_ID=Eval("Type_ID_FK") %>' /> 

通過

<asp:Image ID="Image1" runat="server" ImageUrl='<%# "ImageHandler.ashx?IMG_ID=" + Eval("Image_ID")+"&IMG_type_ID="+Eval("Type_ID_FK")%>' /> 

Answer 3

public void ProcessRequest(HttpContext context) 
    { 
     using (SqlConnection connection = new SqlConnection()) 
     { 
      connection.ConnectionString = "Server=ESLHP280G1P\\SQLEXPRESS; Database=Sample; user id=sa; password=sa@123"; 
      connection.Open(); 
      SqlCommand cmd = new SqlCommand("tblImage_Retrieve", connection); 
      cmd.CommandType = CommandType.StoredProcedure; 
      cmd.Parameters.AddWithValue("@id", context.Request.QueryString["id"]); 
      SqlDataReader dr = cmd.ExecuteReader(); 
      while (dr.Read()) 
      { 
       byte[] bytes = (byte[])dr["photo"]; 
       if (bytes.Length > 0 && bytes != null) 
       { 
        context.Response.ContentType = "jpg"; 
        context.Response.BinaryWrite(bytes); 
       } 
      } 
     } 
    }