为什么单击按钮会没有效果啊~~~~~~~~~~~~


<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %><!DOCTYPE html><html>
<head runat="server">
    <title>SWFUpload Application Demo (ASP.Net 2.0)</title>
<link href="../css/default.css" rel="stylesheet" type="text/css" />
<script type="text/javascript" src="../swfupload/swfupload.js"></script>
<script type="text/javascript" src="js/handlers.js"></script>
<script type="text/javascript">
var swfu;
window.onload = function () {
    swfu = new SWFUpload({
// Backend Settings
upload_url: "upload.aspx",
                post_params : {
                    "ASPSESSID" : "<%=Session.SessionID %>"
                },
                
// File Upload Settings
file_size_limit : "2 MB",
file_types : "*.jpg",
file_types_description : "JPG Images",
file_upload_limit : 0,    // Zero means unlimited // Event Handler Settings - these functions as defined in Handlers.js
//  The handlers are not part of SWFUpload but are part of my website and control how
//  my website reacts to the SWFUpload events.
swfupload_preload_handler : preLoad,
swfupload_load_failed_handler : loadFailed,
file_queue_error_handler : fileQueueError,
file_dialog_complete_handler : fileDialogComplete,
upload_progress_handler : uploadProgress,
upload_error_handler : uploadError,
upload_success_handler : uploadSuccess,
upload_complete_handler : uploadComplete, // Button settings
button_image_url : "images/XPButtonNoText_160x22.png",
button_placeholder_id : "spanButtonPlaceholder",
button_width: 160,
button_height: 22,
button_text : '<span class="button">Select Images <span class="buttonSmall">(2 MB Max)</span></span>',
button_text_style : '.button { font-family: Helvetica, Arial, sans-serif; font-size: 14pt; } .buttonSmall { font-size: 10pt; }',
button_text_top_padding: 1,
button_text_left_padding: 5, // Flash Settings
flash_url : "../swfupload/swfupload.swf", // Relative to this file
flash9_url : "../swfupload/swfupload_FP9.swf", // Relative to this file custom_settings : {
upload_target : "divFileProgressContainer"
}, // Debug Settings
debug: false
});
}
</script>
</head>
<body>
    <form id="form1" runat="server">
<div id="header">   
            <h1 id="logo"><a href="../">SWFUpload</a></h1>   
            <div id="version">v2.1.0 Beta</div>   
        </div>   
    <div id="content">   
                <h2>Application Demo (ASP.Net 2.0)</h2>   
            
        <div id="swfu_container"style="margin: 0px 10px;">   
            <div>   
                <button id="btnBrowse"type="button" style="padding: 5px;" onclick="swfu.selectFile();">选择图片（MAX 2M）</button>   
                <asp:Button ID="btnSave" runat="server" Text="Save Select Images" Width="150px" onclick="btnSave_Click" 
                    />   
                <asp:Button ID="btnClear" runat="server" Text="Clear Select Images"  
                    Width="150px" onclick="btnClear_Click"/></div>   
            <div id="divFileProgressContainer"style="height: 75px;"></div>   
            <div id="thumbnails"></div>   
        </div>   
        </div>   
    </form>
</body>
</html>
swfupload