jQuery AJAX extension ---- automatic abandonment and queue implementation

Automatically give up:

When initiating an AJAX request, if the previous request is not completed, it will be automatically abandoned.

Modify the parameter isAbort = false to turn off this item

 AJAX request queue:

Execute a group of AJAX requests in sequence . After the previous request is successful, execute the next one

 

/**
 * ajax communication class
 * Depends on jQuery 1.6+
 * Extend jQuery's ajax object to implement:
 * 1. Inherit the parameters of the last request,
 * 2. If the last request is not completed, it will be automatically abandoned.
 * 3. Ajax queue requirements
 *
 * by oTwo [email protected]
 * v 1.0 July 31, 2013
 *
 * illustrate:
 * var db = new oTwo.DB(option) option: ajax general settings See comments for details
 * db.xhr jqXHR is a superset of the browser’s XMLHttpRequest object
 * db.queueList array request queue (if saved)
 * db.defaultAjaxOption Object ajax default settings
 *
 * .get(option,[isExtend],[isAbort]) is used to obtain GET requests.
 * .queue(optionArr,[flag]) ajax queue request
 * .setDefault(option) sets the default ajax request parameters
 * .send(option) inherits the default settings and sends the request.
 */
var oTwo = oTwo || {};
oTwo.DB = function(option) {
	this.xhr = {};
	this.queueList = [];
	this.defaultAjaxOption = {
		url: "",
		type: "GET",
		data: "",
		dataType: "json",

		// Timeout (milliseconds) After the timeout, .fail() will be executed, and .done() will not be executed.
		timeout: "",

		//async:false synchronous request
		async: true,

		// cache:false does not cache this page, true caches this page
		cache: false,

		//Force HTTP header to solve Chinese garbled characters
		contentType: 'application/x-www-form-urlencoded; charset=utf-8'
	}
        option = $.extend(true,this.defaultAjaxOption, option);
	this.setDefault(option);
	this.ajaxOption =$.extend(true,{},this.defaultAjaxOption);
}
oTwo.DB.prototype = {
	/**
	 * Used to obtain GET requests. Related settings can be modified through option
	 * .get() repeats the last instruction
	 *
	 * .get(option,[isExtend],[isAbort]) new request
	 * @param Object option ajax setting parameters
	 *----Please refer to http://api.jquery.com/jQuery.ajax/#jQuery-ajax-settings
	 * @param boolean isExtend inherits the parameters of the last request
	 * ---- Default is true, if it is false, this function is turned off.
	 * @param boolean isAbort When initiating an AJAX request, it will automatically give up if the previous request is not completed.
	 * ---- Default is true, if it is false, this function is turned off.
	 *
	 * @return The return object of jqXHR $.ajax(), a superset of the browser's XMLHttpRequest object.
	 *----its common methods
	 * ----jqXHR.done(function(data, textStatus, jqXHR) {}); Request successful
	 * ----jqXHR.fail(function(jqXHR, textStatus, errorThrown) {}); Request failed
	 * ----jqXHR.always(function(data|jqXHR, textStatus, jqXHR|errorThrown) { });Request completed
	 * ---Please refer to http://api.jquery.com/jQuery.ajax/#jqXHR
	 */
	get: function(option, isExtend, isAbort) {
		if (typeof option === "string") {
			option = {
				"url": option
			}
		};

		//Abandon the last unfinished request
		if (this.xhr && this.xhr.done && isAbort !== false) {
			this.xhr.abort();
		};

		// ajaxOption returns to default settings
		if (isExtend === false) {
			this.setDefault();
		};
		this.ajaxOption = $.extend(true,this.ajaxOption, option);
		this.xhr = this.send(this.ajaxOption);
		return this.xhr;
	},

	/**
	 * Please ignore it for internal methods
	 * Inherit the default settings and send the request.
	 * @param Object option ajax setting parameters
	 * @return jqXHR
	 */
	send: function(option) {
		option = $.extend(true, {},this.defaultAjaxOption, option);
		var xhr = $.ajax(option);
		return xhr;
	},

	/**
	 * .setDefault(option)
	 *Set default ajax request parameters
	 * @param Object option ajax setting parameters
	 * @return oTwo.DB
	 *
	 * .setDefault()
	 *Restore to default settings
	 */
	setDefault: function(option) {
		if (!option) {
			this.ajaxOption = $.extend({}, this.defaultAjaxOption);
			return this;
		};

		this.defaultAjaxOption = $.extend(true,{}, option);
		return this;
	},

	/**
	 * ajax queue request
	 * .queue()
	 * Get the current queue
	 *
	 * .queue(optionArr,[flag])
	 * @param array option request array
	 * ---- $.extend(ajaxoption, {callback:function(data){return true}});
	 * ---- ajaxoption: ajax setting parameters will be inherited separately
	 * ---- callback: The callback function after the request is successful. If callback returns false, subsequent requests will be abandoned.
	 * ---- If the request is unsuccessful, subsequent requests will also be abandoned.
	 *
	 * @param boolean isSaveQueue whether to save the request queue
	 * ---- Default true (save)
	 */
	queue: function(queueList, isSaveQueue) {
		if (!queueList) {
			return;
		};
		if (isSaveQueue === false) {
			this.queueList = queueList;
		};
		if (queueList.length === 0) {
			return;
		};

		var ss = queueList.shift(),
			self = this;
		this.send(ss.ajaxoption).done(function(d) {
			var isGoOn = ss.callback(d);
			if (isGoOn !== false) {
				self.queue(queueList, false);
			};
		});
	}
}