3 * Copyright(c) 2006-2009 Ext JS, LLC
5 * http://www.extjs.com/license
8 * @class Ext.data.Field
9 * <p>This class encapsulates the field definition information specified in the field definition objects
10 * passed to {@link Ext.data.Record#create}.</p>
11 * <p>Developers do not need to instantiate this class. Instances are created by {@link Ext.data.Record.create}
12 * and cached in the {@link Ext.data.Record#fields fields} property of the created Record constructor's <b>prototype.</b></p>
14 Ext.data.Field = function(config){
15 if(typeof config == "string"){
16 config = {name: config};
18 Ext.apply(this, config);
24 var st = Ext.data.SortTypes;
25 // named sortTypes are supported, here we look them up
26 if(typeof this.sortType == "string"){
27 this.sortType = st[this.sortType];
30 // set default sortType for strings and dates
34 this.sortType = st.asUCString;
37 this.sortType = st.asDate;
40 this.sortType = st.none;
45 var stripRe = /[\$,%]/g;
47 // prebuilt conversion function for this field, instead of
48 // switching every time we're reading a value
50 var cv, dateFormat = this.dateFormat;
55 cv = function(v){ return v; };
58 cv = function(v){ return (v === undefined || v === null) ? '' : String(v); };
62 return v !== undefined && v !== null && v !== '' ?
63 parseInt(String(v).replace(stripRe, ""), 10) : '';
68 return v !== undefined && v !== null && v !== '' ?
69 parseFloat(String(v).replace(stripRe, ""), 10) : '';
74 cv = function(v){ return v === true || v === "true" || v == 1; };
85 if(dateFormat == "timestamp"){
86 return new Date(v*1000);
88 if(dateFormat == "time"){
89 return new Date(parseInt(v, 10));
91 return Date.parseDate(v, dateFormat);
93 var parsed = Date.parse(v);
94 return parsed ? new Date(parsed) : null;
103 Ext.data.Field.prototype = {
106 * The name by which the field is referenced within the Record. This is referenced by, for example,
107 * the <tt>dataIndex</tt> property in column definition objects passed to {@link Ext.grid.ColumnModel}.
108 * <p>Note: In the simplest case, if no properties other than <tt>name</tt> are required, a field
109 * definition may consist of just a String for the field name.</p>
113 * (Optional) The data type for conversion to displayable value if <tt>{@link Ext.data.Field#convert convert}</tt>
114 * has not been specified. Possible values are
115 * <div class="mdetail-params"><ul>
116 * <li>auto (Default, implies no conversion)</li>
121 * <li>date</li></ul></div>
124 * @cfg {Function} convert
125 * (Optional) A function which converts the value provided by the Reader into an object that will be stored
126 * in the Record. It is passed the following parameters:<div class="mdetail-params"><ul>
127 * <li><b>v</b> : Mixed<div class="sub-desc">The data value as read by the Reader, if undefined will use
128 * the configured <tt>{@link Ext.data.Field#defaultValue defaultValue}</tt>.</div></li>
129 * <li><b>rec</b> : Mixed<div class="sub-desc">The data object containing the row as read by the Reader.
130 * Depending on the Reader type, this could be an Array ({@link Ext.data.ArrayReader ArrayReader}), an object
131 * ({@link Ext.data.JsonReader JsonReader}), or an XML element ({@link Ext.data.XMLReader XMLReader}).</div></li>
134 // example of convert function
135 function fullName(v, record){
136 return record.name.last + ', ' + record.name.first;
139 function location(v, record){
140 return !record.city ? '' : (record.city + ', ' + record.state);
143 var Dude = Ext.data.Record.create([
144 {name: 'fullname', convert: fullName},
145 {name: 'firstname', mapping: 'name.first'},
146 {name: 'lastname', mapping: 'name.last'},
147 {name: 'city', defaultValue: 'homeless'},
149 {name: 'location', convert: location}
152 // create the data store
153 var store = new Ext.data.Store({
154 reader: new Ext.data.JsonReader(
158 totalProperty: 'total'
166 name: { first: 'Fat', last: 'Albert' }
167 // notice no city, state provided in data object
170 name: { first: 'Barney', last: 'Rubble' },
171 city: 'Bedrock', state: 'Stoneridge'
174 name: { first: 'Cliff', last: 'Claven' },
175 city: 'Boston', state: 'MA'
181 * @cfg {String} dateFormat
182 * (Optional) A format string for the {@link Date#parseDate Date.parseDate} function, or "timestamp" if the
183 * value provided by the Reader is a UNIX timestamp, or "time" if the value provided by the Reader is a
184 * javascript millisecond timestamp.
188 * @cfg {Mixed} defaultValue
189 * (Optional) The default value used <b>when a Record is being created by a {@link Ext.data.Reader Reader}</b>
190 * when the item referenced by the <tt>{@link Ext.data.Field#mapping mapping}</tt> does not exist in the data
191 * object (i.e. undefined). (defaults to "")
195 * @cfg {String/Number} mapping
196 * <p>(Optional) A path expression for use by the {@link Ext.data.DataReader} implementation
197 * that is creating the {@link Ext.data.Record Record} to extract the Field value from the data object.
198 * If the path expression is the same as the field name, the mapping may be omitted.</p>
199 * <p>The form of the mapping expression depends on the Reader being used.</p>
200 * <div class="mdetail-params"><ul>
201 * <li>{@link Ext.data.JsonReader}<div class="sub-desc">The mapping is a string containing the javascript
202 * expression to reference the data from an element of the data item's {@link Ext.data.JsonReader#root root} Array. Defaults to the field name.</div></li>
203 * <li>{@link Ext.data.XmlReader}<div class="sub-desc">The mapping is an {@link Ext.DomQuery} path to the data
204 * item relative to the DOM element that represents the {@link Ext.data.XmlReader#record record}. Defaults to the field name.</div></li>
205 * <li>{@link Ext.data.ArrayReader}<div class="sub-desc">The mapping is a number indicating the Array index
206 * of the field's value. Defaults to the field specification's Array position.</div></li>
208 * <p>If a more complex value extraction strategy is required, then configure the Field with a {@link #convert}
209 * function. This is passed the whole row object, and may interrogate it in whatever way is necessary in order to
210 * return the desired data.</p>
214 * @cfg {Function} sortType
215 * (Optional) A function which converts a Field's value to a comparable value in order to ensure
216 * correct sort ordering. Predefined functions are provided in {@link Ext.data.SortTypes}. A custom
217 * sort example:<pre><code>
218 // current sort after sort we want
219 // +-+------+ +-+------+
220 // |1|First | |1|First |
221 // |2|Last | |3|Second|
222 // |3|Second| |2|Last |
223 // +-+------+ +-+------+
225 sortType: function(value) {
226 switch (value.toLowerCase()) // native toLowerCase():
228 case 'first': return 1;
229 case 'second': return 2;
237 * @cfg {String} sortDir
238 * (Optional) Initial direction to sort (<tt>"ASC"</tt> or <tt>"DESC"</tt>). Defaults to
243 * @cfg {Boolean} allowBlank
244 * (Optional) Used for validating a {@link Ext.data.Record record}, defaults to <tt>true</tt>.
245 * An empty value here will cause {@link Ext.data.Record}.{@link Ext.data.Record#isValid isValid}
246 * to evaluate to <tt>false</tt>.