/** Handles history change events. */
function handleHistoryChange(newLocation,
historyData) {
　// if there is no location then display
　// the default, which is the inbox
　if (newLocation == "") {
　　newLocation = "section:inbox";
　}

　// extract the section to display from
　// the location change; newLocation will
　// begin with the word "section:"
　newLocation = newLocation.replace(/section\:/, "");

　// update the browser to respond to this
　// DHTML history change
　displayLocation(newLocation, historyData);
}

/** Displays the given location in the
right-hand side content area. */
function displayLocation(newLocation,sectionData) {
　// get the menu element that was selected
　var selectedElement = document.getElementById(newLocation);

　// clear out the old selected menu item
　var menu = document.getElementById("menu");
　for (var i = 0; i ＜ menu.childNodes.length; i++) {
　　var currentElement = menu.childNodes[i];
　　// see if this is a DOM Element node
　　if (currentElement.nodeType == 1) {
　　　// clear any class name
　　　currentElement.className = "";
　　}
　}

　// cause the new selected menu item to
　// appear differently in the UI
　selectedElement.className = "selected";

　// display the new section in the right-hand
　// side of the screen; determine what
　// our sectionData is

　// display the address book differently by
　// using our local address data we cached
　// earlier
　if (newLocation == "addressbook") {
　　// format and display the address book
　　sectionData = "＜p＞Your addressbook:＜/p＞";
　　sectionData += "＜ul＞";

　　// fetch the address book from the cache
　　// if we don't have it yet
　　if (window.addressBook == undefined) {
　　　window.addressBook = historyStorage.get("addressBook");
　　}

　　// format the address book for display
　　for (var i = 0; i ＜ window.addressBook.length; i++) {
　　　sectionData += "＜li＞"
　　　　+ window.addressBook[i]
　　　　+ "＜/li＞";
　　}

　　sectionData += "＜/ul＞";
　}

　// If there is no sectionData, then
　// remotely retrieve it; in this example
　// we use fake data for everything but the
　// address book
　if (sectionData == null) {
　　// in a real application we would remotely
　　// fetch this section's content
　　sectionData = "＜p＞This is section: "
+ selectedElement.innerHTML + "＜/p＞";
　}

　// update the content's title and main text
　var contentTitle = document.getElementById("content-title");
　var contentValue = document.getElementById("content-value");
　contentTitle.innerHTML = selectedElement.innerHTML;
　contentValue.innerHTML = sectionData;
}

　　您可以下载O'Reilly Mail源代码。

　　结束语

　　现在我们已经了解了如何使用RSH API来使AJAX应用程序支持书签以及后退和前进按钮，并提供了示例代码，您可参考该示例来创建自己的应用程序。希望您能利用书签和历史记录的支持来增强AJAX应用程序。