有两种方法：
第一种：
SWFUpload Version: 2.2.0 Beta 2
Flash Player Version: current
Operating System:Window 7
Browser(s):IE9 in standard conform mode
Description:
We have found that IE9 takes 1 - 2 minutes to display the upload buttons.
This problem can be fixed by adding a "classid" attribute to the object tag which is returned by SWFUpload.getFlashHTML(), i.e. by changing the source to read:
SWFUpload.prototype.getFlashHTML = function () {
// Flash Satay object syntax: http://www.alistapart.com/articles/flashsatay
return ['<object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000" id="', this.movieName, '" type="application/x-shockwave-flash" data="', this.settings.flash_url, '" width="', this.settings.button_width,
'" height="', this.settings.button_height, '" class="swfupload">',
'<param name="wmode" value="', this.settings.button_window_mode , '" />',
'<param name="movie" value="', this.settings.flash_url, '" />',
'<param name="quality" value="high" />',
'<param name="menu" value="false" />',
'<param name="allowScriptAccess" value="always" />',
'<param name="flashvars" value="' + this.getFlashVars() + '" />',
'</object>'].join("");
};
第二种：
SWFUpload.prototype.getFlashHTML = function () {
// Flash Satay object syntax: http://www.alistapart.com/articles/flashsatay
var obj = ['<object id="', this.movieName, '" type="application/x-shockwave-flash" data="', this.settings.flash_url, '" width="', this.settings.button_width, '" height="', this.settings.button_height, '" class="swfupload">'].join(""),
params = [
'<param name="wmode" value="', this.settings.button_window_mode , '" />',
'<param name="movie" value="', this.settings.flash_url, '" />',
'<param name="quality" value="high" />',
'<param name="menu" value="false" />',
'<param name="allowScriptAccess" value="always" />',
'<param name="flashvars" value="', this.getFlashVars(), '" />'
].join("");
if (navigator.userAgent.search(/MSIE/) > -1){
obj = ['<object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000" id="', this.movieName, '" width="', this.settings.button_width, '" height="', this.settings.button_height, '" class="swfupload">'].join("");
params += '<param name="src" value="' + this.settings.flash_url + '" />';
}
return [obj, params, '</object>'].join("");
};
我用的第一种，可以实现。
进一步深入解释：http://blog.longwin.com.tw/2011/10/html-object-flash-classid-2011/