easyuiのdatagridを拡張し、Editorを動的に追加または削除する方法

/**
 * @author   
 * 
 * @requires jQuery,EasyUI
 * 
 *   datagrid，         Editor   
 * 
 *     ，          
 * 
 * datagrid.datagrid('removeEditor', 'cpwd');
 * 
 * datagrid.datagrid('addEditor', [ { field : 'ccreatedatetime', editor : { type : 'datetimebox', options : { editable : false } } }, { field : 'cmodifydatetime', editor : { type : 'datetimebox', options : { editable : false } } } ]);
 * 
 */
$.extend($.fn.datagrid.methods, {
	addEditor : function(jq, param) {
		if (param instanceof Array) {
			$.each(param, function(index, item) {
				var e = $(jq).datagrid('getColumnOption', item.field);
				e.editor = item.editor;
			});
		} else {
			var e = $(jq).datagrid('getColumnOption', param.field);
			e.editor = param.editor;
		}
	},
	removeEditor : function(jq, param) {
		if (param instanceof Array) {
			$.each(param, function(index, item) {
				var e = $(jq).datagrid('getColumnOption', item);
				e.editor = {};
			});
		} else {
			var e = $(jq).datagrid('getColumnOption', param);
			e.editor = {};
		}
	}
});