Java乔晓松-Struts2中文件上传和多文件上传以及获取HttpServletRequest / HttpSession / ServletContext / HttpServletRespons

1.文件上传

第一步：在WEB-INF/lib下加入commons-fileupload-1.2.1.jar、commons-io-1.3.2.jar。这两个文件可以从http://commons.apache.org/下载。

第二步：把form表的enctype设置为：“multipart/form-data“，如下：

<form enctype="multipart/form-data" action="${pageContext.request.contextPath}/xxx.action" method="post">

<input type="file" name="uploadImage">

</form>

第三步：在Action类中添加以下属性，属性红色部分对应于表单中文件字段的名称：

public class HelloWorldAction{

private File uploadImage;//得到上传的文件

private String uploadImageContentType;//得到文件的类型

private String uploadImageFileName;//得到文件的名称

//这里略省了属性的getter/setter方法

public String upload() throws Exception{

String realpath = ServletActionContext.getServletContext().getRealPath("/images");

File file = new File(realpath);

if(!file.exists()) file.mkdirs();

FileUtils.copyFile(uploadImage, new File(file, uploadImageFileName));

return "success";

}

}



2.多文件上传

第一步：在WEB-INF/lib下加入commons-fileupload-1.2.1.jar、commons-io-1.3.2.jar。这两个文件可以从http://commons.apache.org/下载。

第二步：把form表的enctype设置为：“multipart/form-data“，如下：

<form enctype="multipart/form-data" action="${pageContext.request.contextPath}/xxx.action" method="post">

<input type="file" name="uploadImages">

<input type="file" name="uploadImages">

</form>

第三步：在Action类中添加以下属性，属性红色部分对应于表单中文件字段的名称：

public class HelloWorldAction{

private File[] uploadImages;//得到上传的文件

private String[] uploadImagesContentType;//得到文件的类型

private String[] uploadImagesFileName;//得到文件的名称

//这里略省了属性的getter/setter方法

public String upload() throws Exception{

String realpath = ServletActionContext.getServletContext().getRealPath("/images");

File file = new File(realpath);

if(!file.exists()) file.mkdirs();

for(int i=0 ;i<uploadImages.length; i++){ File uploadImage = uploadImages[i];

FileUtils.copyFile(uploadImage, new File(file, uploadImagesFileName[i]));

}

return "success";

}}





3.获取HttpServletRequest / HttpSession / ServletContext / HttpServletResponse对象

方法一，通过ServletActionContext.类直接获取：

public String rsa() throws Exception{

HttpServletRequest request = ServletActionContext.getRequest();

ServletContext servletContext = ServletActionContext.getServletContext();

request.getSession()

HttpServletResponse response = ServletActionContext.getResponse();

return "scope";

}

方法二，实现指定接口，由struts框架运行时注入：

public class HelloWorldAction implements ServletRequestAware, ServletResponseAware, ServletContextAware{

private HttpServletRequest request;

private ServletContext servletContext;

private HttpServletResponse response;

public void setServletRequest(HttpServletRequest req) {

this.request=req;

}

public void setServletResponse(HttpServletResponse res) {

this.response=res;

}

public void setServletContext(ServletContext ser) {

this.servletContext=ser;

}

}