EXTJS data store mapping

HTML

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JavaScript

Ext.define('SafeJson', {
    extend: 'Ext.data.reader.Json',
    alias : 'reader.safejson',
    /**
     * @private
     * Returns an accessor function for the given property string. Gives support for properties such as the following:
     * 'someProperty'
     * 'some.property'
     * 'some["property"]'
     * This is used by buildExtractors to create optimized extractor functions when casting raw data into model instances.
     */
    createAccessor: (function() {
        var re = /[\[\.]/;

        return function(expr) {
            if (Ext.isEmpty(expr)) {
                return Ext.emptyFn;
            }
            if (Ext.isFunction(expr)) {
                return expr;
            }
            if (this.useSimpleAccessors !== true) {
                var i = String(expr).search(re);
                if (i >= 0) {
                    if (i > 0) {    // Check all property chain for existence. Return null if any level does not exist.
                        var a = [];
                        var l = expr.split('.');
                        var r = '';
                        for (var w in l) {
                            r = r + '.' + l[w];
                            a.push('obj' + r);
                        }
                        var v = "(" + a.join(" && ") + ") ? obj." + expr + " : null";
                        return Ext.functionFactory('obj', 'return (' + v + ')');
                    } else {
                        return Ext.functionFactory('obj', 'return obj' + (i > 0 ? '.' : '') + expr);
                    }
                }
            }
            return function(obj) {
                return obj[expr];
            };
        };
    }()),
    
        /**
     * @private
     * @method
     * Returns an accessor expression for the passed Field. Gives support for properties such as the following:
     *
     * - 'someProperty'
     * - 'some.property'
     * - 'some["property"]'
     *
     * This is used by buildExtractors to create...