這次教大家的是在H5裡如何用JS和servlet來實現檔案上傳，不過有一個前提條件，必須要是h5和jsp3.0版本，因為用到了新屬性，取得file物件和後台得到part物件。
下面給大家看一個案例列
前台jsp
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "https://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="jquery-3.2.1.min.js"></script>
</head>
<body>
<p>
name:<input type="text" id="name"/>
文件：<input type="file" id="file"/>
<br>
<button id="btu" onclick="btu()">提交</button>
</p>
</body>
<script>
function btu(){
var name=$("#name").val();
var file=$("#file")[0].files[0];//新特性，获取文件对象
var fordata=new FormData();//新特性，得到formData对象，把获取的值扔进去，相当于map
fordata.append("name",name);
fordata.append("file",file);
console.log(file)
$.ajax({
url:"/war-2/UpdataFile",
data:fordata,
cache:false,
processData:false, //必须写
contentType:false, //必须写
type:"post",
success:function(data){
}
})
}
</script>
</html>後台java
package up;
import java.io.File;
import java.io.IOException;
import java.util.Collection;
import javax.servlet.ServletException;
import javax.servlet.annotation.MultipartConfig;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.Part;
/**
* Servlet implementation class UpdataFile
*/
@MultipartConfig(location="E:/")
@WebServlet("/UpdataFile")
public class UpdataFile extends HttpServlet {
private static final long serialVersionUID = 1L;
private File file;
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
System.out.println("1111111111");
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
//得到part对象，这个对象有write的方法，直接写到指定位置。但是千万别忘了写@MultipartConfig(location="E:/")注解，不指定位置默认是写到注解指定的位置。
Part part = request.getPart("file");
//普通的字段可以采用常规的getparamter的方法得到。
System.out.println(new String(request.getParameter("name").getBytes("iso-8859-1"),"utf-8"));
System.out.println(part.getName());
System.out.println(part.getHeader("Content-Disposition"));
System.out.println(part.getSize());
String fileName = getFileNameFromPart(part);
part.write(fileName);
}
//截取文件名
public String getFileNameFromPart(Part part) {
String header = part.getHeader("Content-Disposition");
String fileName = header.substring(header.indexOf("filename=\"")+10, header.lastIndexOf("\""));
return fileName;
}
}以上是h5裡js和servlet實作檔案上傳的實作步驟的詳細內容。更多資訊請關注PHP中文網其他相關文章！
