这些天我一直在努力解决这个问题,也许你肯定比我知道的更多,你可以帮助我....然后我尝试更好地解释。
我有一个 javascript 文件,它通过库 d3.js 构建 html 代码页并用其他代码替换它,每个部分都有不同的功能......该页面不会收费(Ajax)。在某些时候,我需要允许用户将图像上传到他们的个人资料图片,所以我确保 html 代码诱饵
<input type="file" id="file">
和一个
<input type = "button" onclick = "javaScript: performAjaxSubmit ()">
PerformAjaxSubmit 函数 () 通过 xmlHttpRequest 级别 2 将数据发送到 Java Servlet,据我了解,它不仅可以发送字符串,还可以发送更复杂的内容,例如文件。
功能如下:
function performAjaxSubmit() {
var sampleFile = document.getElementById("file").files[0];
var formdata = new FormData();
formdata.append("sampleFile", sampleFile);
var xhr = new XMLHttpRequest();
xhr.open("POST", "http://127.0.0.1:8080/Prova/Upload", true);
xhr.send(formdata);
xhr.onload = function(e) {
if (this.status == 200) {
alert(this.responseText);
}
};
}
Servlet 中的代码是这样的:
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
// Check that we have a file upload request
System.out.println(request.getAttribute("username"));
isMultipart = ServletFileUpload.isMultipartContent(request);
response.setContentType("text/html");
java.io.PrintWriter out = response.getWriter( );
DiskFileItemFactory factory = new DiskFileItemFactory();
// maximum size that will be stored in memory
factory.setSizeThreshold(maxMemSize);
// Location to save data that is larger than maxMemSize.
factory.setRepository(new File("C:/Users/Marty/workspaceJEE/Prova/WebContent/imm/utenti"));
filePath="C:/Users/Marty/workspaceJEE/Prova/WebContent/imm/utenti";
// Create a new file upload handler
ServletFileUpload upload = new ServletFileUpload(factory);
// maximum file size to be uploaded.
upload.setSizeMax( maxFileSize );
try{
// Parse the request to get file items.
List fileItems = upload.parseRequest(request);
// Process the uploaded file items
Iterator i = fileItems.iterator();
while ( i.hasNext () )
{
FileItem fi = (FileItem)i.next();
if ( !fi.isFormField () )
{
// Get the uploaded file parameters
String fieldName = fi.getFieldName();
String fileName = fi.getName();
String contentType = fi.getContentType();
boolean isInMemory = fi.isInMemory();
long sizeInBytes = fi.getSize();
// Write the file
if( fileName.lastIndexOf("\\") >= 0 ){
file = new File( filePath +"/"+
fileName.substring( fileName.lastIndexOf("\\"))) ;
}else{
System.out.println(filePath +
fileName.substring(fileName.lastIndexOf("\\")+1));
file = new File( filePath +"/"+
fileName.substring(fileName.lastIndexOf("\\")+1)) ;
}
fi.write( file ) ;
}
}
}catch(Exception ex) {
System.out.println(ex);
}
}
现在(对不起,如果问题有点长)它可以工作,但问题是图像保存在我为我提供命令的路径中:
factory.setRepository(new File("C:/Users/Marty/workspaceJEE/Prova/WebContent/imm/utenti"));
那么如何远程保存呢?也就是说,一旦我加载了这样的 Altrevista 的站点,我如何确保它们不是 pià 保存到 C 中,而是保存在项目的文件夹中?
我希望我解释了。我正在使用 Apache Tomcat v7.0。提前致谢!