用戶控件上的ASP.NET調用方法

Question

我創建了如下的用戶控件來上傳圖像。 在后面的代碼中，我有保存圖像的方法。

<%@ Control Language="C#" AutoEventWireup="true" CodeBehind="UCImageUploader.ascx.cs"
    Inherits="WebApplicationFor_ABC.UCImageUploader" %>
<div>
    <asp:FileUpload ID="FileUploadImage" runat="server" />
    <asp:Image ID="ImageThumbnail" runat="server" />
    <asp:Label ID="LblMsg" runat="server" Text=""></asp:Label>
<asp:CheckBox ID="CheckBoxDelete" runat="server" Text="Delete"/>

</div>

后面的代碼如下

 public partial class UCImageUploader : System.Web.UI.UserControl
    {
        public bool SaveImg()
        {
                        //file field isn't empty
        if (FileUploadImage.PostedFile != null)
        {

            //check file size
            HttpPostedFile img = FileUploadImage.PostedFile;

            if (img.ContentLength == 0) // no file uploaded
            {
                msg = "No file was uploaded";
                LblMsg.Text = msg;
                return false;
            }
            else if (img.ContentLength > fileSizeInKB * 1024) // file size exceeds limit
            {
                msg = "File size exceeds the limit. Max is " + fileSizeInKB + "KB";
                LblMsg.Text = msg;
                return false;
            }
            else // accepted file size
            {
                //check file extension jpg,jpeg,BMP

                string[] fileExtensions = { "jpg", "jpeg", "bmp" };

                if (!fileExtensions.Contains(Path.GetExtension(img.FileName).ToLower()))
                {
                    msg = "File extension must be of jpg,jpeg,bmp";
                    LblMsg.Text = msg;
                    return false;
                }

            }
        }
        msg = "Valid File";
        LblMsg.Text = msg;
        return valid;
    }

在另一個按鈕的單擊事件上，我想調用此SaveImg()方法並保存圖像。 問題是因為回發圖像返回為空。 我怎樣才能解決這個問題。

Answer 1

為了訪問圖像，請勿通過文件上載控件來執行此操作，例如

FileUploadImage.SaveAs(savePath);