来自:http://www.blogjava.net/sxyx2008/archive/2010/11/02/336826.html
由于项目需求,在处理文件上传时需要使用到文件的异步上传。这里使用Jquery Ajax File Uploader这个组件下载地址:http://www.phpletter.com/download_project_version.php?version_id=6
服务器端采用struts2来处理文件上传。
所需环境:
jquery.js
ajaxfileupload.js
struts2所依赖的jar包
及struts2-json-plugin-2.1.8.1.jar
编写文件上传的Action
package com.ajaxfile.action;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;
@SuppressWarnings("serial")
public class FileAction extends ActionSupport {
private File file;
private String fileFileName;
private String fileFileContentType;
private String message = "你已成功上传文件";
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
public File getFile() {
return file;
}
public void setFile(File file) {
this.file = file;
}
public String getFileFileName() {
return fileFileName;
}
public void setFileFileName(String fileFileName) {
this.fileFileName = fileFileName;
}
public String getFileFileContentType() {
return fileFileContentType;
}
public void setFileFileContentType(String fileFileContentType) {
this.fileFileContentType = fileFileContentType;
}
@SuppressWarnings("deprecation")
@Override
public String execute() throws Exception {
String path = ServletActionContext.getRequest().getRealPath("/upload");
try {
File f = this.getFile();
if(this.getFileFileName().endsWith(".exe")){
message="对不起,你上传的文件格式不允许!!!";
return ERROR;
}
FileInputStream inputStream = new FileInputStream(f);
FileOutputStream outputStream = new FileOutputStream(path + "/"+ this.getFileFileName());
byte[] buf = new byte[1024];
int length = 0;
while ((length = inputStream.read(buf)) != -1) {
outputStream.write(buf, 0, length);
}
inputStream.close();
outputStream.flush();
} catch (Exception e) {
e.printStackTrace();
message = "对不起,文件上传失败了!!!!";
}
return SUCCESS;
}
}
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;
@SuppressWarnings("serial")
public class FileAction extends ActionSupport {
private File file;
private String fileFileName;
private String fileFileContentType;
private String message = "你已成功上传文件";
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
public File getFile() {
return file;
}
public void setFile(File file) {
this.file = file;
}
public String getFileFileName() {
return fileFileName;
}
public void setFileFileName(String fileFileName) {
this.fileFileName = fileFileName;
}
public String getFileFileContentType() {
return fileFileContentType;
}
public void setFileFileContentType(String fileFileContentType) {
this.fileFileContentType = fileFileContentType;
}
@SuppressWarnings("deprecation")
@Override
public String execute() throws Exception {
String path = ServletActionContext.getRequest().getRealPath("/upload");
try {
File f = this.getFile();
if(this.getFileFileName().endsWith(".exe")){
message="对不起,你上传的文件格式不允许!!!";
return ERROR;
}
FileInputStream inputStream = new FileInputStream(f);
FileOutputStream outputStream = new FileOutputStream(path + "/"+ this.getFileFileName());
byte[] buf = new byte[1024];
int length = 0;
while ((length = inputStream.read(buf)) != -1) {
outputStream.write(buf, 0, length);
}
inputStream.close();
outputStream.flush();
} catch (Exception e) {
e.printStackTrace();
message = "对不起,文件上传失败了!!!!";
}
return SUCCESS;
}
}
struts.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.1//EN" "http://struts.apache.org/dtds/struts-2.1.dtd">
<struts>
<package name="struts2" extends="json-default">
<action name="fileUploadAction" class="com.ajaxfile.action.FileAction">
<result type="json" name="success">
<param name="contentType">
text/html
</param>
</result>
<result type="json" name="error">
<param name="contentType">
text/html
</param>
</result>
</action>
</package>
</struts>
<!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.1//EN" "http://struts.apache.org/dtds/struts-2.1.dtd">
<struts>
<package name="struts2" extends="json-default">
<action name="fileUploadAction" class="com.ajaxfile.action.FileAction">
<result type="json" name="success">
<param name="contentType">
text/html
</param>
</result>
<result type="json" name="error">
<param name="contentType">
text/html
</param>
</result>
</action>
</package>
</struts>
注意结合Action观察struts.xml中result的配置。
contentType参数是一定要有的,否则浏览器总是提示将返回的JSON结果另存为文件,不会交给ajaxfileupload处理。这是因为struts2
JSON Plugin默认的contentType为application/json,而ajaxfileupload则要求为text/html。
文件上传的jsp页面
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<script type="text/javascript" src="js/jquery.js"></script>
<script type="text/javascript" src="js/ajaxfileupload.js"></script>
<script type="text/javascript">
function ajaxFileUpload()
{
$("#loading")
.ajaxStart(function(){
$(this).show();
})//开始上传文件时显示一个图片
.ajaxComplete(function(){
$(this).hide();
});//文件上传完成将图片隐藏起来
$.ajaxFileUpload
(
{
url:‘fileUploadAction.action‘,//用于文件上传的服务器端请求地址
secureuri:false,//一般设置为false
fileElementId:‘file‘,//文件上传空间的id属性 <input type="file" id="file" name="file" />
dataType: ‘json‘,//返回值类型 一般设置为json
success: function (data, status) //服务器成功响应处理函数
{
alert(data.message);//从服务器返回的json中取出message中的数据,其中message为在struts2中action中定义的成员变量
if(typeof(data.error) != ‘undefined‘)
{
if(data.error != ‘‘)
{
alert(data.error);
}else
{
alert(data.message);
}
}
},
error: function (data, status, e)//服务器响应失败处理函数
{
alert(e);
}
}
)
return false;
}
</script>
</head>
<body>
<img src="loading.gif" id="loading" style="display: none;">
<input type="file" id="file" name="file" />
<br />
<input type="button" value="上传" onclick="return ajaxFileUpload();">
</body>
</html>
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
<script type="text/javascript" src="js/jquery.js"></script>
<script type="text/javascript" src="js/ajaxfileupload.js"></script>
<script type="text/javascript">
function ajaxFileUpload()
{
$("#loading")
.ajaxStart(function(){
$(this).show();
})//开始上传文件时显示一个图片
.ajaxComplete(function(){
$(this).hide();
});//文件上传完成将图片隐藏起来
$.ajaxFileUpload
(
{
url:‘fileUploadAction.action‘,//用于文件上传的服务器端请求地址
secureuri:false,//一般设置为false
fileElementId:‘file‘,//文件上传空间的id属性 <input type="file" id="file" name="file" />
dataType: ‘json‘,//返回值类型 一般设置为json
success: function (data, status) //服务器成功响应处理函数
{
alert(data.message);//从服务器返回的json中取出message中的数据,其中message为在struts2中action中定义的成员变量
if(typeof(data.error) != ‘undefined‘)
{
if(data.error != ‘‘)
{
alert(data.error);
}else
{
alert(data.message);
}
}
},
error: function (data, status, e)//服务器响应失败处理函数
{
alert(e);
}
}
)
return false;
}
</script>
</head>
<body>
<img src="loading.gif" id="loading" style="display: none;">
<input type="file" id="file" name="file" />
<br />
<input type="button" value="上传" onclick="return ajaxFileUpload();">
</body>
</html>
注意观察<body>中的代码,并没有form表单。只是在按钮点击的时候触发ajaxFileUpload()方法。需要注意的是js文件引入的先后顺序,ajaxfileupload.js依赖于jquery因此你知道的。