1. 定义一个上传限制数量 var uploadLimit = 3;

2. 点击页面的删除图片成功后，将uploadLimit++操作

3. 通过uploadify的settings方式重置上传限制数量,例如

$('#file_upload').uploadify('settings','uploadLimit', ++uploadLimit);

 参考的http://www.xuebuyuan.com/1422566.html

实际中用于删除图片

$(document).on('click','.Upload-img i',function(){	 	$data = $('#file_upload').data('uploadify');//获取上传文件的属性    	settings = $data.settings;    	//settings.uploadLimit++;//增加上传数量    	var uploadLimit=settings.uploadLimit;//获取当前设置的上传文件数限制    	var _this = $(this);   		$('#file_upload').uploadify('settings','uploadLimit', ++uploadLimit);//重置增加上传文件数    	$.each(pictures,function(index,item){			if(item.picUrl==_this.prev('img').attr('picurl')){				pictures.splice(index,1);							return false;			}		});		console.log(pictures)    	$(this).parent().remove();    	console.log(settings.uploadLimit);	 })