点击按钮出现上传文件框

<!-- 隐藏的文件上传组件，点击IMPORT时让该DIV显示即可-->
		<div id="upLoadForm" align="center" class="area" style="width:200 height:200 visibility:hidden">
		<form name="upform"  method="POST" enctype="multipart/form-data" target="myFrame"><!--target是为了能将处理于IFRAME中处理，实现无刷新-->
         <input type ="file" name="file" id="file"/>
		 <input type="hidden" name="textDatasImport" value="tt"><!--隐藏域，用于传递前台文本框信息-->
        <input type="button" value="上传" onclick="handle('import')"/>
         </form>
		</div>

 在HTML中插入此隐藏DIV

//打开上传窗口
function openUploadWin() 
{ 
    if(!bSelected)
	 {
	window.alert("请选择要导出的区域!");
	return;
	 }
  upLoadForm.style.left=document.body.scrollLeft+document.body.clientWidth/2-100;
  upLoadForm.style.top=document.body.scrollTop+document.body.clientHeight/2-100;
  /*upLoadForm.innerHTML=" <form name="upform"  method="POST" enctype="multipart/form-data">"
  +"<input type ="file" name="file" id="file"/>"
  +"<input type="button" value="上传" onclick="handle('import')"/>"
  +"</form>";
*/

　upLoadForm.style.visibility="visible";
  
} 

 以上是让上传框显示的JS代码

  document.upform.textDatasImport.value=value;//将值赋给上传文件隐藏文本框
			init();
		   upLoadForm.style.visibility="hidden";
           document.upform.action="importFromExcel";
		   document.upform.submit();

 点击上传按钮，执行上代码，则会将前台的value赋给upform的hidden文本框textDatasImport,并在后台进行处理

得到此值的方法

要用到SMARTUPLOAD

SmartUpload upload = new SmartUpload();
		try {
			upload.initialize(this.getServletConfig(), request, response);
			// 允许上传的文件类型
			upload.setAllowedFilesList("doc,xls,");
			// 拒绝上传的文件类型
			upload.setDeniedFilesList("exe,bat,jsp");
			// 允许上传文件的单个最大大小
			upload.setMaxFileSize(1024 * 1024 * 20);
			// 允许上传文件的最大大小总和
			
			// 上传数据
			upload.upload();

			StringBuffer fullFileName = null;// 保存到服务器上的文件名(带路径)
			File suFile = upload.getFiles().getFile(0);
			fullFileName = new StringBuffer("data.xls");// 填写 文件的路径
			suFile.saveAs(fullFileName.toString(), SmartUpload.SAVE_PHYSICAL);

		} catch (Exception e) {
			e.printStackTrace();
			return;
		}
       //获得FORM是文件上传时的隐藏域传值问题
		Request req = upload.getRequest();
		String texts = (String) req.getParameter("textDatasImport"); //即可得到数据