connection.js

ajax框架extjs是一套完整的富客户端解决方案

            }else if(this.autoAbort !== false){
                this.abort();
            }
            if((method == 'GET' || o.xmlData || o.jsonData) && p){
                url += (url.indexOf('?') != -1 ? '&' : '?') + p;
                p = '';
            }
            this.transId = Ext.lib.Ajax.request(method, url, cb, p, o);
            return this.transId;
        }else{
            Ext.callback(o.callback, o.scope, [o, null, null]);
            return null;
        }
    },

    /**
     * Determine whether this object has a request outstanding.
     * @param {Number} transactionId (Optional) defaults to the last transaction
     * @return {Boolean} True if there is an outstanding request.
     */
    isLoading : function(transId){
        if(transId){
            return Ext.lib.Ajax.isCallInProgress(transId);
        }else{
            return this.transId ? true : false;
        }
    },

    /**
     * Aborts any outstanding request.
     * @param {Number} transactionId (Optional) defaults to the last transaction
     */
    abort : function(transId){
        if(transId || this.isLoading()){
            Ext.lib.Ajax.abort(transId || this.transId);
        }
    },

    // private
    handleResponse : function(response){
        this.transId = false;
        var options = response.argument.options;
        response.argument = options ? options.argument : null;
        this.fireEvent("requestcomplete", this, response, options);
        Ext.callback(options.success, options.scope, [response, options]);
        Ext.callback(options.callback, options.scope, [options, true, response]);
    },

    // private
    handleFailure : function(response, e){
        this.transId = false;
        var options = response.argument.options;
        response.argument = options ? options.argument : null;
        this.fireEvent("requestexception", this, response, options, e);
        Ext.callback(options.failure, options.scope, [response, options]);
        Ext.callback(options.callback, options.scope, [options, false, response]);
    },

    // private
    doFormUpload : function(o, ps, url){
        var id = Ext.id();
        var frame = document.createElement('iframe');
        frame.id = id;
        frame.name = id;
        frame.className = 'x-hidden';
        if(Ext.isIE){
            frame.src = Ext.SSL_SECURE_URL;
        }
        document.body.appendChild(frame);

        if(Ext.isIE){
           document.frames[id].name = id;
        }

        var form = Ext.getDom(o.form);
        form.target = id;
        form.method = 'POST';
        form.enctype = form.encoding = 'multipart/form-data';
        if(url){
            form.action = url;
        }

        var hiddens, hd;
        if(ps){ // add dynamic params
            hiddens = [];
            ps = Ext.urlDecode(ps, false);
            for(var k in ps){
                if(ps.hasOwnProperty(k)){
                    hd = document.createElement('input');
                    hd.type = 'hidden';
                    hd.name = k;
                    hd.value = ps[k];
                    form.appendChild(hd);
                    hiddens.push(hd);
                }
            }
        }

        function cb(){
            var r = {  // bogus response object
                responseText : '',
                responseXML : null
            };

            r.argument = o ? o.argument : null;

            try { //
                var doc;
                if(Ext.isIE){
                    doc = frame.contentWindow.document;
                }else {
                    doc = (frame.contentDocument || window.frames[id].document);
                }
                if(doc && doc.body){
                    r.responseText = doc.body.innerHTML;
                }
                if(doc && doc.XMLDocument){
                    r.responseXML = doc.XMLDocument;
                }else {
                    r.responseXML = doc;
                }
            }
            catch(e) {
                // ignore
            }

            Ext.EventManager.removeListener(frame, 'load', cb, this);

            this.fireEvent("requestcomplete", this, r, o);

            Ext.callback(o.success, o.scope, [r, o]);
            Ext.callback(o.callback, o.scope, [o, true, r]);

            setTimeout(function(){Ext.removeNode(frame);}, 100);
        }

        Ext.EventManager.on(frame, 'load', cb, this);
        form.submit();

        if(hiddens){ // remove dynamic params
            for(var i = 0, len = hiddens.length; i < len; i++){
                Ext.removeNode(hiddens[i]);
            }
        }
    }
});

/**
 * @class Ext.Ajax
 * @extends Ext.data.Connection
 * Global Ajax request class.  Provides a simple way to make Ajax requests with maximum flexibility.  Example usage:
 * <pre><code>
// Basic request
Ext.Ajax.request({
   url: 'foo.php',
   success: someFn,
   failure: otherFn,
   headers: {
       'my-header': 'foo'
   },
   params: { foo: 'bar' }
});

// Simple ajax form submission
Ext.Ajax.request({
    form: 'some-form',
    params: 'foo=bar'
});

// Default headers to pass in every request
Ext.Ajax.defaultHeaders = {
    'Powered-By': 'Ext'
};

// Global Ajax events can be handled on every request!
Ext.Ajax.on('beforerequest', this.showSpinner, this);
</code></pre>
 * @singleton
 */
Ext.Ajax = new Ext.data.Connection({
    /**
     * @cfg {String} url @hide
     */
    /**
     * @cfg {Object} extraParams @hide
     */
    /**
     * @cfg {Object} defaultHeaders @hide
     */
    /**
     * @cfg {String} method (Optional) @hide
     */
    /**
     * @cfg {Number} timeout (Optional) @hide
     */
    /**
     * @cfg {Boolean} autoAbort (Optional) @hide
     */

    /**
     * @cfg {Boolean} disableCaching (Optional) @hide
     */

    /**
     * @property  disableCaching
     * True to add a unique cache-buster param to GET requests. (defaults to true)
     * @type Boolean
     */
    /**
     * @property  url
     * The default URL to be used for requests to the server. (defaults to undefined)
     * @type String
     */
    /**
     * @property  extraParams
     * An object containing properties which are used as
     * extra parameters to each request made by this object. (defaults to undefined)
     * @type Object
     */
    /**
     * @property  defaultHeaders
     * An object containing request headers which are added to each request made by this object. (defaults to undefined)
     * @type Object
     */
    /**
     * @property  method
     * The default HTTP method to be used for requests. Note that this is case-sensitive and should be all caps (defaults
     * to undefined; if not set but parms are present will use "POST," otherwise "GET.")
     * @type String
     */
    /**
     * @property  timeout
     * The timeout in milliseconds to be used for requests. (defaults to 30000)
     * @type Number
     */

    /**
     * @property  autoAbort
     * Whether a new request should abort any pending requests. (defaults to false)
     * @type Boolean
     */
    autoAbort : false,

    /**
     * Serialize the passed form into a url encoded string
     * @param {String/HTMLElement} form
     * @return {String}
     */
    serializeForm : function(form){
        return Ext.lib.Ajax.serializeForm(form);
    }
});