springmvc Ajax表单上传文件案例

<form id='formId' method='post'  enctype="multipart/form-data">

<table>
<tr>
<td class='n_type'>名称</td>
<td><input id='n_project_name' name='project_name'></td>
</tr>
<tr>
<td class='n_type'>文件:</td>
<td>
<input id="lefile" name="lefile" type="file" style="display:none">
<div class="input-append">
<input  id="file_name" name="file_name" type="text" >
<a class="btn" onclick="$('input[id=lefile]').click();" >上传</a>
</div>
</td>
</tr>
</table>
</form>

$('input[id=le
4000
file]').change(function() {
$('#file_name').val($(this).val());
});

$("#flowconfirm").click(function() {

$.ajax({
cache: true,
type: "POST",
url:url,
data: new FormData(document.getElementById("formId")),
// 告诉jQuery不要去处理发送的数据
processData : false,
// 告诉jQuery不要去设置Content-Type请求头
contentType : false,
error: function(request) {
alert("Connection error");
},
success: function(data) {

}
});
});

@RequestMapping(value = "/addProject" , method = RequestMethod.POST)
@ResponseBody
public Object addProject(Project project , HttpServletRequest request){
//获取上传的文件
MultipartHttpServletRequest multipartRequest = (MultipartHttpServletRequest) request;
MultipartFile file = multipartRequest.getFile("lefile");
String fileName = file.getOriginalFilename();
project.setFile_name(fileName);
//保存
try {
File targetFile = new File(projectFilePath, fileName);
if(!targetFile.exists()){
targetFile.mkdirs();
}
file.transferTo(targetFile);
} catch (Exception e) {
e.printStackTrace();
}
return null;
}

<bean id="multipartResolver"
class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
<!-- 上传文件大小控制 -->
<property name="maxUploadSize" value="10240000" />
<property name="resolveLazily" value="true" />
<property name="defaultEncoding" value="UTF-8" />
</bean>