当提交表单的时候怎么保留text框中的数据,java servlet

发布网友 发布时间：2022-08-04 21:58

我来回答

共5个回答

热心网友 时间：2024-02-02 04:53

这个，如果你用ajax异步提交的话，那么最简单不过了~~~~~代码的话：
只需要在HTML里，加上：
<script type="text/javascript" language="javascript">
var http_request = false;
function makePOSTRequest(url, parameters) {
http_request = false;
if (window.XMLHttpRequest) { // Mozilla, Safari,...
http_request = new XMLHttpRequest();
if (http_request.overrideMimeType) { // set type accordingly to anticipated content type
http_request.overrideMimeType('text/xml');
http_request.overrideMimeType('text/html');
}
} else if (window.ActiveXObject) {
try {
http_request = new ActiveXObject("Msxml2.XMLHTTP");
} catch(e) {
try {
http_request = new ActiveXObject("Microsoft.XMLHTTP");
} catch(e) {}
}
}
if (!http_request) {
alert('Cannot create XMLHTTP instance');
return false;
}
http_request.onreadystatechange = alertContents;
http_request.open('POST', url, true);
http_request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
http_request.setRequestHeader("Content-length", parameters.length);
http_request.setRequestHeader("Connection", "close");
http_request.send(parameters);
}
function alertContents() {
if (http_request.readyState == 4) {
if (http_request.status == 200) {
alert(http_request.responseText);
result = http_request.responseText;
document.getElementById('myspan').innerHTML = result;
} else {
alert('There was a problem with the request.');
}
}
}
function get(obj) {
var poststr = "mytextarea1=" + encodeURI(document.getElementById("mytextarea1").value) + "&mytextarea2=" + encodeURI(document.getElementById("mytextarea2").value);
makePOSTRequest('post.php', poststr);
}
</script>
<form action="javascript:get(document.getElementById('myform'));" name="myform"
id="myform">
<textarea id="mytextarea1">
my test 1 2 3
</textarea>
<textarea id="mytextarea2">
my test2 4 5 6
</textarea>
<br>
<input type="button" name="button" value="Submit" onclick="javascript:get(this.parentNode);">
<input type="submit" name="button" value="Normal Submit Button">
</form>
<br>
<br>
Server-Response:
<br>
<hr>
<span name="myspan" id="myspan">
</span>
<hr>
==============================================
以上是参考实例，可对应修改<script>里的语句追问我去，这是神马啊，哪里贴来的啊

热心网友 时间：2024-02-02 04:53

表单提交给Servlet后，进行相关操作，将提交的数据封装成对象，比如 username password
user.setUsername(username);
user.setPassword(password);
request.setAttribute("user", user);
JSP页面代码:
<input type="text" name="username" value="${user.username}" />
<input type="password" name="password" value="${user.password}" />

热心网友 时间：2024-02-02 04:54

servlet 中 request取得数据，然后在把他设置进request就可以在页面上获得了
String xx = request.getParameter("xxxx");
request.setAttribute("xxxx",xx);

页面部分的话 jsp代码
<%=request.getAttribute("xxxx")%> 或者别的方法也有，随便用就是了（request是jsp页面的隐含对象）追问不是要jsp代码，要java的

追答上面那不就是java的

热心网友 时间：2024-02-02 04:54

servlet处理完之后再把数据丢给jsp
jsp渲染的时候写出来就行了。

热心网友 时间：2024-02-02 04:55

具体怎么做我也不太清
不过要实现这个的话肯定要用Cookie
朝这个方向找去吧......