ASIHTTPRequest系列(三)：文件上传

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五、文件上传

1、服务端

文件上传需要服务端的配合。我们可在本机搭建tomcat测试环境。关于tomcat在MacOSX下的安装配置，参考作者另一博文《安装Tomcat到Mac OSX》。

打开Eclipse，新建web工程。在其中新建一个ServletUploadServlet：

import java.io.*;

import java.util.*;

importjavax.servlet.ServletException;

importjavax.servlet.http.HttpServlet;

importjavax.servlet.http.HttpServletRequest;

importjavax.servlet.http.HttpServletResponse;

importorg.apache.commons.fileupload.FileItem;

importorg.apache.commons.fileupload.disk.DiskFileItemFactory;

importorg.apache.commons.fileupload.servlet.ServletFileUpload;

public class UploadServletextends HttpServlet {

private boolean isMultipart;

private String filePath,title;

private int maxFileSize = 500 * 1024;

private int maxMemSize = 4 * 1024;

private File file ;

public void init( ){

// 从web.xml的context_param中获得上传文件目录（/data）.

filePath =

getServletContext().getInitParameter("file-upload");

}

public voiddoPost(HttpServletRequest request,

HttpServletResponse response)

throws ServletException,java.io.IOException {

// 检查表单是否带有 ENCTYPE="multipart/form-data"

isMultipart =ServletFileUpload.isMultipartContent(request);

response.setContentType("text/html");

response.setCharacterEncoding("GBK");

java.io.PrintWriter out = response.getWriter( );

if( !isMultipart ){

out.println("<html>");

out.println("<head>");

out.println("<title>Servlet upload</title>");

out.println("</head>");

out.println("<body>");

out.println("<p>No file uploaded</p>");

out.println("</body>");

out.println("</html>");

return;

}

DiskFileItemFactoryfactory = new DiskFileItemFactory();

// 内存最大可缓存尺寸

factory.setSizeThreshold(maxMemSize);

// 指定当数据超过内存最大可缓存尺寸时，临时文件的目录

factory.setRepository(new File(filePath+"temp"));

// 文件上传对象

ServletFileUpload upload = new ServletFileUpload(factory);

// 设置文件上传最大允许尺寸

upload.setSizeMax( maxFileSize );

try{

out.println("<%@pagecontentType='text/html; charset=GBK'%>");

out.println("<html>");

out.println("<head>");

out.println("<title>Servletupload</title>");

out.println("</head>");

out.println("<body>");

// 获取multipart/form-data内容，其中每个field被分成不同part

List fileItems = upload.parseRequest(request);

// 枚举每个field

Iterator i = fileItems.iterator();

while ( i.hasNext () )

{

FileItem fi = (FileItem)i.next();

if ( !fi.isFormField() ) // 如果field为File

{

// 获取field的name或id

String fieldName = fi.getFieldName();

String fileName = fi.getName();

// 文件名中文处理

fileName=newString(fileName.getBytes(),"gbk");

out.println("file name:"+fileName+"<br>");

String contentType = fi.getContentType();

boolean isInMemory= fi.isInMemory();

long sizeInBytes= fi.getSize();

// 把上传数据写入本地磁盘

if(fileName.lastIndexOf("//") >= 0 ){

file = new File( filePath +

fileName.substring( fileName.lastIndexOf("//"))) ;

}else{

file = new File( filePath +

fileName.substring(fileName.lastIndexOf("//")+1)) ;

}

fi.write( file ) ;

out.println("Uploaded Filename:" + fileName + "<br>");

}else{// 如果field为Form Field

title=fi.getFieldName();

if(title.equals("title")){

title=new String(fi.get(),"gbk");

out.println("title:"+title+"<br>");

}

out.println("</body>");

out.println("</html>");

}catch(Exception ex) {

System.out.println(ex);

}

public voiddoGet(HttpServletRequest request,

HttpServletResponse response)

throws ServletException,java.io.IOException {

throw new ServletException("GET method used with " +

getClass( ).getName( )+": POSTmethod required.");

}

再新建一个upload.jsp页面作为测试：

<%@page contentType="text/html; charset=GBK" language="java" import="java.util.*"%>

<html>

<head>

<title>fbysss UploadBean 示例</title>

</head>

</form>

</html>

将工程部署到tomcat中，启动tomcat，访问http://localhost:8080/test/upload.jsp，显示界面如下：

选择一个文件进行上传，然后到/data目录下检查该文件是否上传成功。

2、iPhone客户端

新建类，选择UIViewController subclass，并勾上“WithXIB for user interface”，命名为 UploadViewController。

用 IB 打开 Xib 文件，在其中拖入1个 UIToolBar 、1个UIBarButtonItem 和1个 UIWebView、1个UIProgressView：

在Xcode中声明必要的变量和 IBOutlet／IBAction:

#import <UIKit/UIKit.h>

#import "ASIFormDataRequest.h"

#import "ASIHTTPRequest.h"

@interface UploadViewController : UIViewController {

UIBarItem* button;

UIWebView* webView;

UIProgressView* progress;

ASIFormDataRequest *request;

NSURL *url;

}

@property(retain,nonatomic)IBOutlet UIBarItem* button;

@property(retain,nonatomic)IBOutlet UIProgressView* progress;

@property(retain,nonatomic)IBOutlet UIWebView* webView;

-(IBAction)go;

-(void)printBytes:(NSString*)str encoding:(NSStringEncoding)enc;

@end

将所有出口正确地连接到 UpdateController.xib 中，保存。

打开MainWindow.xib，拖一个UIViewController进去并将其Identifier改为UpdateController，再将它连接到Window对象的的rootViewController。

编写 UIButton 的 Touch up inside 事件代码如下：

-(IBAction)go{

NSString* s=@"哈哈哈";

url=[NSURL URLWithString:@"http://localhost:8080/test/UploadServlet"];

request = [ASIFormDataRequest requestWithURL:url];

// 字符串使用 GBK 编码，因为 servlet 只识别GBK

NSStringEncoding enc=CFStringConvertEncodingToNSStringEncoding(kCFStringEncodingMacChineseSimp);

[request setStringEncoding:enc];

[self printBytes:s encoding:enc];// 打印GBK编码字符

[request setPostValue:s forKey:@"title"];

[request setFile:@"/Users/kmyhy/Documents/iphone/Iphone开发介绍.doc" forKey:@"attach"];

[request setDelegate:self];

[request setDidFinishSelector:@selector(responseComplete)];

[request setDidFailSelector:@selector(responseFailed)];

[button setEnabled:NO];

[request startSynchronous];

}

-(void)responseComplete{

// 请求响应结束，返回responseString

NSString*responseString = [request responseString];

[webView loadHTMLString:responseStringbaseURL:url];

[button setEnabled:YES];

}

-(void)respnoseFailed{

//请求响应失败，返回错误信息

NSError *error = [request error];

[webView loadHTMLString:[error description] baseURL:url];

[button setEnabled:YES];

}

-(void)printBytes:(NSString *)strencoding:(NSStringEncoding)enc{

NSLog(@"defaultCStringEncoding:%d",[NSString defaultCStringEncoding]);

// 根据给定的字符编码，打印出编码后的字符数组

const char *bytes=[str cStringUsingEncoding:enc];

for (int i=0;i<strlen(bytes);i++){

NSLog(@"%d%X",(i+1),bytes[i]);

}

编译、运行。点击go按钮，程序运行效果如下：