Javascript 复选框值的持久性
我有一个带有几个复选框的页面。我选中了其中的一些复选框并转到下一页，当我回到这一页时，这些复选框需要保持选中状态，就像导航到另一页之前一样。需要使用Javascript来完成。任何线索？？？您需要在页面请求之间保留它们。您可以使用会话或cookie来完成此操作。您使用的是哪种类型的服务器，以及哪种类型的服务器端语言 前面关于SO的问题涉及从JavaScript编写/读取cookieJavascript 复选框值的持久性,javascript,checkbox,persistence,back,Javascript,Checkbox,Persistence,Back,我有一个带有几个复选框的页面。我选中了其中的一些复选框并转到下一页，当我回到这一页时，这些复选框需要保持选中状态，就像导航到另一页之前一样。需要使用Javascript来完成。任何线索？？？您需要在页面请求之间保留它们。您可以使用会话或cookie来完成此操作。您使用的是哪种类型的服务器，以及哪种类型的服务器端语言 前面关于SO的问题涉及从JavaScript编写/读取cookie 如果您仅限于JavaScript，而没有服务器端语言，我认为您只能通过读/写cookie来维护状态。正如其他
函数createCookie（名称、值、天数）{
如果（天）{
变量日期=新日期（）；
date.setTime（date.getTime（）+（天*24*60*60*1000））；
var expires=“；expires=“+date.togmString（）；
}
else var expires=“”；
document.cookie=name+“=”+value+expires+“path=/”；
}
函数readCookie（名称）{
变量nameEQ=name+“=”；
var ca=document.cookie.split（“；”）；
对于（变量i=0；i<body onload="restorePersistedCheckBoxes()">
<input type="checkbox" id="check1" onclick="persistCheckBox(this)" />
<input type="checkbox" id="check2" onclick="persistCheckBox(this)" />
<input type="checkbox" id="check3" onclick="persistCheckBox(this)" />
<input type="button" value="Check cookie"
onclick="alert(document.cookie)" />
<input type="button" value="Clear cookie"
onclick="clearPersistenceCookie()" />
<script type="text/javascript">
// This function reads the cookie and checks/unchecks all elements
// that have been stored inside. It will NOT mess with checkboxes
// whose state has not yet been recorded at all.
function restorePersistedCheckBoxes() {
var aStatus = getPersistedCheckStatus();
for(var i = 0; i < aStatus.length; i++) {
var aPair = aStatus[i].split(':');
var el = document.getElementById(aPair[0]);
if(el) {
el.checked = aPair[1] == '1';
}
}
}
// This function takes as input an input type="checkbox" element and
// stores its check state in the persistence cookie. It is smart
// enough to add or replace the state as appropriate, and not affect
// the stored state of other checkboxes.
function persistCheckBox(el) {
var found = false;
var currentStateFragment = el.id + ':' + (el.checked ? '1' : '0');
var aStatus = getPersistedCheckStatus();
for(var i = 0; i < aStatus.length; i++) {
var aPair = aStatus[i].split(':');
if(aPair[0] == el.id) {
// State for this checkbox was already present; replace it
aStatus[i] = currentStateFragment;
found = true;
break;
}
}
if(!found) {
// State for this checkbox wasn't present; add it
aStatus.push(currentStateFragment);
}
// Now that the array has our info stored, persist it
setPersistedCheckStatus(aStatus);
}
// This function simply returns the checkbox persistence status as
// an array of strings. "Hides" the fact that the data is stored
// in a cookie.
function getPersistedCheckStatus() {
var stored = getPersistenceCookie();
return stored.split(',');
}
// This function stores an array of strings that represents the
// checkbox persistence status. "Hides" the fact that the data is stored
// in a cookie.
function setPersistedCheckStatus(aStatus) {
setPersistenceCookie(aStatus.join(','));
}
// Retrieve the value of the persistence cookie.
function getPersistenceCookie()
{
// cookies are separated by semicolons
var aCookie = document.cookie.split('; ');
for (var i=0; i < aCookie.length; i++)
{
// a name/value pair (a crumb) is separated by an equal sign
var aCrumb = aCookie[i].split('=');
if ('JS_PERSISTENCE_COOKIE' == aCrumb[0])
return unescape(aCrumb[1]);
}
return ''; // cookie does not exist
}
// Sets the value of the persistence cookie.
// Does not affect other cookies that may be present.
function setPersistenceCookie(sValue) {
document.cookie = 'JS_PERSISTENCE_COOKIE=' + escape(sValue);
}
// Removes the persistence cookie.
function clearPersistenceCookie() {
document.cookie = 'JS_PERSISTENCE_COOKIE=' +
';expires=Fri, 31 Dec 1999 23:59:59 GMT;';
}
</script>
</body>
//此函数读取cookie并选中/取消选中所有元素
//已经被储存在里面了。它不会弄乱复选框
//他的状态还没有被记录下来。
函数restorePersistedCheckBox（）{
var aStatus=getPersistedCheckStatus（）；
对于（变量i=0；i<body onload="restorePersistedCheckBoxes()">
<input type="checkbox" id="check1" onclick="persistCheckBox(this)" />
<input type="checkbox" id="check2" onclick="persistCheckBox(this)" />
<input type="checkbox" id="check3" onclick="persistCheckBox(this)" />
<input type="button" value="Check cookie"
onclick="alert(document.cookie)" />
<input type="button" value="Clear cookie"
onclick="clearPersistenceCookie()" />
<script type="text/javascript">
// This function reads the cookie and checks/unchecks all elements
// that have been stored inside. It will NOT mess with checkboxes
// whose state has not yet been recorded at all.
function restorePersistedCheckBoxes() {
var aStatus = getPersistedCheckStatus();
for(var i = 0; i < aStatus.length; i++) {
var aPair = aStatus[i].split(':');
var el = document.getElementById(aPair[0]);
if(el) {
el.checked = aPair[1] == '1';
}
}
}
// This function takes as input an input type="checkbox" element and
// stores its check state in the persistence cookie. It is smart
// enough to add or replace the state as appropriate, and not affect
// the stored state of other checkboxes.
function persistCheckBox(el) {
var found = false;
var currentStateFragment = el.id + ':' + (el.checked ? '1' : '0');
var aStatus = getPersistedCheckStatus();
for(var i = 0; i < aStatus.length; i++) {
var aPair = aStatus[i].split(':');
if(aPair[0] == el.id) {
// State for this checkbox was already present; replace it
aStatus[i] = currentStateFragment;
found = true;
break;
}
}
if(!found) {
// State for this checkbox wasn't present; add it
aStatus.push(currentStateFragment);
}
// Now that the array has our info stored, persist it
setPersistedCheckStatus(aStatus);
}
// This function simply returns the checkbox persistence status as
// an array of strings. "Hides" the fact that the data is stored
// in a cookie.
function getPersistedCheckStatus() {
var stored = getPersistenceCookie();
return stored.split(',');
}
// This function stores an array of strings that represents the
// checkbox persistence status. "Hides" the fact that the data is stored
// in a cookie.
function setPersistedCheckStatus(aStatus) {
setPersistenceCookie(aStatus.join(','));
}
// Retrieve the value of the persistence cookie.
function getPersistenceCookie()
{
// cookies are separated by semicolons
var aCookie = document.cookie.split('; ');
for (var i=0; i < aCookie.length; i++)
{
// a name/value pair (a crumb) is separated by an equal sign
var aCrumb = aCookie[i].split('=');
if ('JS_PERSISTENCE_COOKIE' == aCrumb[0])
return unescape(aCrumb[1]);
}
return ''; // cookie does not exist
}
// Sets the value of the persistence cookie.
// Does not affect other cookies that may be present.
function setPersistenceCookie(sValue) {
document.cookie = 'JS_PERSISTENCE_COOKIE=' + escape(sValue);
}
// Removes the persistence cookie.
function clearPersistenceCookie() {
document.cookie = 'JS_PERSISTENCE_COOKIE=' +
';expires=Fri, 31 Dec 1999 23:59:59 GMT;';
}
</script>
</body>