datasource-debug.js

这是YUI的源码及相关示例。里面有很多很炫的Javascript效果。

                        for (j = fieldParsers.length - 1; j >= 0; --j) {
                            var p = fieldParsers[j].key;
                            rec[p] = fieldParsers[j].parser(rec[p]);
                            if (rec[p] === undefined) {
                                rec[p] = null;
                            }
                        }
                        results[i] = rec;
                    }
                //}
            }
            else {
                results = resultsList;
            }

            for (key in metaFields) {
                if (lang.hasOwnProperty(metaFields,key)) {
                    path = buildPath(metaFields[key]);
                    if (path) {
                        v = walkPath(path, oFullResponse);
                        oParsedResponse.meta[key] = v;
                    }
                }
            }

        } else {
            YAHOO.log("JSON data could not be parsed: " +
                    lang.dump(oFullResponse), "error", this.toString());

            oParsedResponse.error = true;
        }

        oParsedResponse.results = results;
    }
    else {
        YAHOO.log("JSON data could not be parsed: " +
                lang.dump(oFullResponse), "error", this.toString());
        oParsedResponse.error = true;
    }

    return oParsedResponse;
},

/**
 * Overridable method parses an HTML TABLE element reference into a response object.
 * Data is parsed out of TR elements from all TBODY elements. 
 *
 * @method parseHTMLTableData
 * @param oRequest {Object} Request object.
 * @param oFullResponse {Object} The full HTML element reference from the live database.
 * @return {Object} Parsed response object with the following properties<br>
 *     - results (Array) Array of parsed data results<br>
 *     - error (Boolean) True if there was an error
 */
parseHTMLTableData : function(oRequest, oFullResponse) {
    var bError = false;
    var elTable = oFullResponse;
    var fields = this.responseSchema.fields;
    var oParsedResponse = {results:[]};

    // Iterate through each TBODY
    for(var i=0; i<elTable.tBodies.length; i++) {
        var elTbody = elTable.tBodies[i];

        // Iterate through each TR
        for(var j=elTbody.rows.length-1; j>-1; j--) {
            var elRow = elTbody.rows[j];
            var oResult = {};
            
            for(var k=fields.length-1; k>-1; k--) {
                var field = fields[k];
                var key = (lang.isValue(field.key)) ? field.key : field;
                var data = elRow.cells[k].innerHTML;

                // Backward compatibility
                if(!field.parser && field.converter) {
                    field.parser = field.converter;
                    YAHOO.log("The field property converter has been deprecated" +
                            " in favor of parser", "warn", this.toString());
                }
                var parser = (typeof field.parser === 'function') ?
                    field.parser :
                    DS.Parser[field.parser+''];
                if(parser) {
                    data = parser.call(this, data);
                }
                // Safety measure
                if(data === undefined) {
                    data = null;
                }
                oResult[key] = data;
            }
            oParsedResponse.results[j] = oResult;
        }
    }

    if(bError) {
        YAHOO.log("HTML TABLE data could not be parsed: " +
                lang.dump(oFullResponse), "error", this.toString());
        oParsedResponse.error = true;
    }
    else {
        YAHOO.log("Parsed HTML TABLE data is " +
                lang.dump(oParsedResponse), "info", this.toString());
    }
    return oParsedResponse;
}

};

// DataSourceBase uses EventProvider
lang.augmentProto(DS, util.EventProvider);



/****************************************************************************/
/****************************************************************************/
/****************************************************************************/

/**
 * LocalDataSource class for in-memory data structs including JavaScript arrays,
 * JavaScript object literals (JSON), XML documents, and HTML tables.
 *
 * @namespace YAHOO.util
 * @class YAHOO.util.LocalDataSource
 * @extends YAHOO.util.DataSourceBase 
 * @constructor
 * @param oLiveData {HTMLElement}  Pointer to live data.
 * @param oConfigs {object} (optional) Object literal of configuration values.
 */
util.LocalDataSource = function(oLiveData, oConfigs) {
    this.dataType = DS.TYPE_LOCAL;
    
    if(oLiveData) {
        if(YAHOO.lang.isArray(oLiveData)) { // array
            this.responseType = DS.TYPE_JSARRAY;
        }
         // xml
        else if(oLiveData.nodeType && oLiveData.nodeType == 9) {
            this.responseType = DS.TYPE_XML;
        }
        else if(oLiveData.nodeName && (oLiveData.nodeName.toLowerCase() == "table")) { // table
            this.responseType = DS.TYPE_HTMLTABLE;
            oLiveData = oLiveData.cloneNode(true);
        }    
        else if(YAHOO.lang.isString(oLiveData)) { // text
            this.responseType = DS.TYPE_TEXT;
        }
        else if(YAHOO.lang.isObject(oLiveData)) { // json
            this.responseType = DS.TYPE_JSON;
        }
    }
    else {
        oLiveData = [];
        this.responseType = DS.TYPE_JSARRAY;
    }
    
    this.constructor.superclass.constructor.call(this, oLiveData, oConfigs); 
};

// LocalDataSource extends DataSourceBase
lang.extend(util.LocalDataSource, DS);

// Copy static members to LocalDataSource class
lang.augmentObject(util.LocalDataSource, DS);













/****************************************************************************/
/****************************************************************************/
/****************************************************************************/

/**
 * FunctionDataSource class for JavaScript functions.
 *
 * @namespace YAHOO.util
 * @class YAHOO.util.FunctionDataSource
 * @extends YAHOO.util.DataSourceBase  
 * @constructor
 * @param oLiveData {HTMLElement}  Pointer to live data.
 * @param oConfigs {object} (optional) Object literal of configuration values.
 */
util.FunctionDataSource = function(oLiveData, oConfigs) {
    this.dataType = DS.TYPE_JSFUNCTION;
    oLiveData = oLiveData || function() {};
    
    this.constructor.superclass.constructor.call(this, oLiveData, oConfigs); 
};

// FunctionDataSource extends DataSourceBase
lang.extend(util.FunctionDataSource, DS, {

/////////////////////////////////////////////////////////////////////////////
//
// FunctionDataSource public methods
//
/////////////////////////////////////////////////////////////////////////////

/**
 * Overriding method passes query to a function. The returned response is then
 * forwarded to the handleResponse function.
 *
 * @method makeConnection
 * @param oRequest {Object} Request object.
 * @param oCallback {Object} Callback object literal.
 * @param oCaller {Object} (deprecated) Use oCallback.scope.
 * @return {Number} Transaction ID.
 */
makeConnection : function(oRequest, oCallback, oCaller) {
    var tId = DS._nTransactionId++;
    this.fireEvent("requestEvent", {tId:tId,request:oRequest,callback:oCallback,caller:oCaller});

    // Pass the request in as a parameter and
    // forward the return value to the handler
    var oRawResponse = this.liveData(oRequest);
    
    // Try to sniff data type if it has not been defined
    if(this.responseType === DS.TYPE_UNKNOWN) {
        if(YAHOO.lang.isArray(oRawResponse)) { // array
            this.responseType = DS.TYPE_JSARRAY;
        }
         // xml
        else if(oRawResponse && oRawResponse.nodeType && oRawResponse.nodeType == 9) {
            this.responseType = DS.TYPE_XML;
        }
        else if(oRawResponse && oRawResponse.nodeName && (oRawResponse.nodeName.toLowerCase() == "table")) { // table
            this.responseType = DS.TYPE_HTMLTABLE;
        }    
        else if(YAHOO.lang.isObject(oRawResponse)) { // json
            this.responseType = DS.TYPE_JSON;
        }
        else if(YAHOO.lang.isString(oRawResponse)) { // text
            this.responseType = DS.TYPE_TEXT;
        }
    }

    this.handleResponse(oRequest, oRawResponse, oCallback, oCaller, tId);
    return tId;
}

});

// Copy static members to FunctionDataSource class
lang.augmentObject(util.FunctionDataSource, DS);













/****************************************************************************/
/****************************************************************************/
/****************************************************************************/

/**
 * ScriptNodeDataSource class for accessing remote data via the YUI Get Utility. 
 *
 * @namespace YAHOO.util
 * @class YAHOO.util.ScriptNodeDataSource
 * @extends YAHOO.util.DataSourceBase  
 * @constructor
 * @param oLiveData {HTMLElement}  Pointer to live data.
 * @param oConfigs {object} (optional) Object literal of configuration values.
 */
util.ScriptNodeDataSource = function(oLiveData, oConfigs) {
    this.dataType = DS.TYPE_SCRIPTNODE;
    oLiveData = oLiveData || "";
    
    this.constructor.superclass.constructor.call(this, oLiveData, oConfigs); 
};

// ScriptNodeDataSource extends DataSourceBase
lang.extend(util.ScriptNodeDataSource, DS, {

/////////////////////////////////////////////////////////////////////////////
//
// ScriptNodeDataSource public properties
//
/////////////////////////////////////////////////////////////////////////////

/**
 * Alias to YUI Get Utility, to allow implementers to use a custom class.
 *
 * @property getUtility
 * @type Object
 * @default YAHOO.util.Get
 */
getUtility : util.Get,

/**
 * Defines request/response management in the following manner:
 * <dl>
 *     <!--<dt>queueRequests</dt>
 *     <dd>If a request is already in progress, wait until response is returned before sending the next request.</dd>
 *     <dt>cancelStaleRequests</dt>
 *     <dd>If a request is already in progress, cancel it before sending the next request.</dd>-->
 *     <dt>ignoreStaleResponses</dt>
 *     <dd>Send all requests, but handle only the response for the most recently sent request.</dd>
 *     <dt>allowAll</dt>
 *     <dd>Send all requests and handle all responses.</dd>
 * </dl>
 *
 * @property asyncMode
 * @type String
 * @default "allowAll"
 */
asyncMode : "allowAll",

/**
 * Callback string parameter name sent to the remote script. By default,
 * requests are sent to
 * &#60;URI&#62;?&#60;scriptCallbackParam&#62;=callbackFunction
 *
 * @property scriptCallbackParam
 * @type String
 * @default "callback"
 */
scriptCallbackParam : "callback",


/////////////////////////////////////////////////////////////////////////////
//
// ScriptNodeDataSource public methods
//
/////////////////////////////////////////////////////////////////////////////

/**
 * Creates a request callback that gets appended to the script URI. Implementers
 * can customize this string to match their server's query syntax.
 *
 * @method generateRequestCallback
 * @return {String} String fragment that gets appended to script URI that 
 * specifies the callback function 
 */
generateRequestCallback : function(id) {
    return "&" + this.scriptCallbackParam + "=YAHOO.util.ScriptNodeDataSource.callbacks["+id+"]" ;
},

/**
 * Overriding method passes query to Get Utility. The returned
 * response is then forwarded to the handleResponse function.
 *
 * @method makeConnection
 * @param oRequest {Object} Request object.
 * @param oCallback {Object} Callback object literal.
 * @param oCaller {Object} (deprecated) Use oCallback.scope.
 * @return {Number} Transaction ID.
 */
makeConnection : function(oRequest, oCallback, oCaller) {
    var tId = DS._nTransactionId++;
    this.fireEvent("requestEvent", {tId:tId,request:oRequest,callback:oCallback,caller:oCaller});
    
    // If there are no global pending requests, it is safe to purge global callback stack and global counter
    if(util.ScriptNodeDataSource._nPending === 0) {
        util.ScriptNodeDataSource.callbacks = [];
        util.ScriptNodeDataSource._nId = 0;
    }
    
    // ID for this request
    var id = util.ScriptNodeDataSource._nId;
    util.ScriptNodeDataSource._nId++;
    
    // Dynamically add handler function with a closure to the callback stack
    var oSelf = this;
    util.ScriptNodeDataSource.callbacks[id] = function(oRawResponse) {
        if((oSelf.asyncMode !== "ignoreStaleResponses")||
                (id === util.ScriptNodeDataSource.callbacks.length-1)) { // Must ignore sta