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37 </script><div id="top-block" class="top-block"><h1 id="clsTitle" class="cls"><a href="../source/Field3.html#Ext-data.Field" target="_blank">Ext.data.Field</a></h1></div><div id="docContent"><div id="doc-overview-content"><div class="lft"><p>Fields are used to define what a Model is. They aren't instantiated directly - instead, when we create a class
38 that extends <a href="Ext.data.Model.html" rel="Ext.data.Model" class="docClass">Ext.data.Model</a>, it will automatically create a Field instance for each field configured in a
39 <a href="Ext.data.Model.html" rel="Ext.data.Model" class="docClass">Model</a>. For example, we might set up a model like this:</p>
44 <pre class="prettyprint"><code>Ext.define('User', {
45 extend: 'Ext.data.Model',
48 {name: 'age', type: 'int'},
49 {name: 'gender', type: 'string', defaultValue: 'Unknown'}
57 <p>Four fields will have been created for the User Model - name, email, age and gender. Note that we specified a
58 couple of different formats here; if we only pass in the string name of the field (as with name and email), the
59 field is set up with the 'auto' type. It's as if we'd done this instead:</p>
64 <pre class="prettyprint"><code>Ext.define('User', {
65 extend: 'Ext.data.Model',
67 {name: 'name', type: 'auto'},
68 {name: 'email', type: 'auto'},
69 {name: 'age', type: 'int'},
70 {name: 'gender', type: 'string', defaultValue: 'Unknown'}
78 <p><u>Types and conversion</u></p>
83 <p>The <a href="Ext.data.Field.html#type" rel="Ext.data.Field#type" class="docClass">type</a> is important - it's used to automatically convert data passed to the field into the correct
84 format. In our example above, the name and email fields used the 'auto' type and will just accept anything that is
85 passed into them. The 'age' field had an 'int' type however, so if we passed 25.4 this would be rounded to 25.</p>
90 <p>Sometimes a simple type isn't enough, or we want to perform some processing when we load a Field's data. We can
91 do this using a <a href="Ext.data.Field.html#convert" rel="Ext.data.Field#convert" class="docClass">convert</a> function. Here, we're going to create a new field based on another:</p>
96 <pre class="prettyprint">Ext.define('User', {
97 extend: 'Ext.data.Model',
100 {name: 'age', type: 'int'},
101 {name: 'gender', type: 'string', defaultValue: 'Unknown'},
105 convert: function(value, record) {
106 var fullName = record.get('name'),
107 splits = fullName.split(" "),
108 firstName = splits[0];
120 <p>Now when we create a new User, the firstName is populated automatically based on the name:</p>
125 <pre class="prettyprint">var ed = Ext.ModelManager.create({name: 'Ed Spencer'}, 'User');
127 console.log(ed.get('firstName')); //logs 'Ed', based on our convert function
133 <p>In fact, if we log out all of the data inside ed, we'll see this:</p>
138 <pre class="prettyprint">console.log(ed.data);
153 <p>The age field has been given a default of zero because we made it an int type. As an auto field, email has
154 defaulted to an empty string. When we registered the User model we set gender's <a href="Ext.data.Field.html#defaultValue" rel="Ext.data.Field#defaultValue" class="docClass">defaultValue</a> to 'Unknown'
155 so we see that now. Let's correct that and satisfy ourselves that the types work as we expect:</p>
160 <pre class="prettyprint">ed.set('gender', 'Male');
161 ed.get('gender'); //returns 'Male'
164 ed.get('age'); //returns 25 - we wanted an int, not a float, so no decimal places allowed
167 <div class="members"><div class="m-cfgs"><div class="definedBy">Defined By</div><a name="configs"></a><h3 class="cfg p">Config Options</h3><h4 class="cfgGroup">Other Configs</h4><div id="config-convert" class="member f ni"><a href="Ext.data.Field.html#config-convert" rel="config-convert" class="expand more ar"><span> </span></a><div class="title"><div class="meta"><a href="Ext.data.Field.html" class="definedIn docClass">Ext.data.Field</a><br/><a href="../source/Field3.html#Ext-data.Field-cfg-convert" class="viewSource">view source</a></div><a name="convert"></a><a name="config-convert"></a><a href="Ext.data.Field.html#" rel="config-convert" class="cls expand">convert</a><span> : Function</span></div><div class="description"><div class="short">(Optional) A function which converts the value provided by the Reader into an object that will be stored
168 in the Model...</div><div class="long"><p>(Optional) A function which converts the value provided by the Reader into an object that will be stored
169 in the Model. It is passed the following parameters:<div class="mdetail-params"><ul>
170 <li><b>v</b> : Mixed<div class="sub-desc">The data value as read by the Reader, if undefined will use
171 the configured <code><a href="Ext.data.Field.html#defaultValue" rel="Ext.data.Field#defaultValue" class="docClass">defaultValue</a></code>.</div></li>
172 <li><b>rec</b> : Ext.data.Model<div class="sub-desc">The data object containing the Model as read so far by the
173 Reader. Note that the Model may not be fully populated at this point as the fields are read in the order that
174 they are defined in your <a href="Ext.data.Field.html#fields" rel="Ext.data.Field#fields" class="docClass">fields</a> array.</div></li>
177 <pre><code>// example of convert function
178 function fullName(v, record){
179 return record.name.last + ', ' + record.name.first;
182 function location(v, record){
183 return !record.city ? '' : (record.city + ', ' + record.state);
187 extend: 'Ext.data.Model',
189 {name: 'fullname', convert: fullName},
190 {name: 'firstname', mapping: 'name.first'},
191 {name: 'lastname', mapping: 'name.last'},
192 {name: 'city', defaultValue: 'homeless'},
194 {name: 'location', convert: location}
198 // create the data store
199 var store = new Ext.data.Store({
205 totalProperty: 'total'
211 name: { first: 'Fat', last: 'Albert' }
212 // notice no city, state provided in data object
215 name: { first: 'Barney', last: 'Rubble' },
216 city: 'Bedrock', state: 'Stoneridge'
219 name: { first: 'Cliff', last: 'Claven' },
220 city: 'Boston', state: 'MA'
225 </div></div></div><div id="config-dateFormat" class="member ni"><a href="Ext.data.Field.html#config-dateFormat" rel="config-dateFormat" class="expand more ar"><span> </span></a><div class="title"><div class="meta"><a href="Ext.data.Field.html" class="definedIn docClass">Ext.data.Field</a><br/><a href="../source/Field3.html#Ext-data.Field-cfg-dateFormat" class="viewSource">view source</a></div><a name="dateFormat"></a><a name="config-dateFormat"></a><a href="Ext.data.Field.html#" rel="config-dateFormat" class="cls expand">dateFormat</a><span> : String</span></div><div class="description"><div class="short">(Optional) Used when converting received data into a Date when the type is specified as "date".
228 A format string for...</div><div class="long"><p>(Optional) Used when converting received data into a Date when the <a href="Ext.data.Field.html#type" rel="Ext.data.Field#type" class="docClass">type</a> is specified as <code>"date"</code>.</p>
231 <p>A format string for the <a href="Ext.Date.html#parse" rel="Ext.Date#parse" class="docClass">Ext.Date.parse</a> function, or "timestamp" if the
232 value provided by the Reader is a UNIX timestamp, or "time" if the value provided by the Reader is a
233 javascript millisecond timestamp. See <a href="Date.html" rel="Date" class="docClass">Date</a></p>
235 </div></div></div><div id="config-defaultValue" class="member ni"><a href="Ext.data.Field.html#config-defaultValue" rel="config-defaultValue" class="expand more ar"><span> </span></a><div class="title"><div class="meta"><a href="Ext.data.Field.html" class="definedIn docClass">Ext.data.Field</a><br/><a href="../source/Field3.html#Ext-data.Field-cfg-defaultValue" class="viewSource">view source</a></div><a name="defaultValue"></a><a name="config-defaultValue"></a><a href="Ext.data.Field.html#" rel="config-defaultValue" class="cls expand">defaultValue</a><span> : Mixed</span></div><div class="description"><div class="short">(Optional) The default value used when a Model is being created by a Reader
236 when the item referenced by the mapping d...</div><div class="long"><p>(Optional) The default value used <b>when a Model is being created by a <a href="Ext.data.reader.Reader.html" rel="Ext.data.reader.Reader" class="docClass">Reader</a></b>
237 when the item referenced by the <code><a href="Ext.data.Field.html#mapping" rel="Ext.data.Field#mapping" class="docClass">mapping</a></code> does not exist in the data
238 object (i.e. undefined). (defaults to "")</p>
239 </div></div></div><div id="config-mapping" class="member ni"><a href="Ext.data.Field.html#config-mapping" rel="config-mapping" class="expand more ar"><span> </span></a><div class="title"><div class="meta"><a href="Ext.data.Field.html" class="definedIn docClass">Ext.data.Field</a><br/><a href="../source/Field3.html#Ext-data.Field-cfg-mapping" class="viewSource">view source</a></div><a name="mapping"></a><a name="config-mapping"></a><a href="Ext.data.Field.html#" rel="config-mapping" class="cls expand">mapping</a><span> : String/Number</span></div><div class="description"><div class="short">(Optional) A path expression for use by the Ext.data.reader.Reader implementation
240 that is creating the Model to extra...</div><div class="long"><p>(Optional) A path expression for use by the <a href="Ext.data.reader.Reader.html" rel="Ext.data.reader.Reader" class="docClass">Ext.data.reader.Reader</a> implementation
241 that is creating the <a href="Ext.data.Model.html" rel="Ext.data.Model" class="docClass">Model</a> to extract the Field value from the data object.
242 If the path expression is the same as the field name, the mapping may be omitted.</p>
245 <p>The form of the mapping expression depends on the Reader being used.</p>
248 <div class="mdetail-params"><ul>
249 <li><a href="Ext.data.reader.Json.html" rel="Ext.data.reader.Json" class="docClass">Ext.data.reader.Json</a><div class="sub-desc">The mapping is a string containing the javascript
250 expression to reference the data from an element of the data item's <a href="Ext.data.reader.Json.html#root" rel="Ext.data.reader.Json#root" class="docClass">root</a> Array. Defaults to the field name.</div></li>
251 <li><a href="Ext.data.reader.Xml.html" rel="Ext.data.reader.Xml" class="docClass">Ext.data.reader.Xml</a><div class="sub-desc">The mapping is an <a href="Ext.DomQuery.html" rel="Ext.DomQuery" class="docClass">Ext.DomQuery</a> path to the data
252 item relative to the DOM element that represents the <a href="Ext.data.reader.Xml.html#record" rel="Ext.data.reader.Xml#record" class="docClass">record</a>. Defaults to the field name.</div></li>
253 <li><a href="Ext.data.reader.Array.html" rel="Ext.data.reader.Array" class="docClass">Ext.data.reader.Array</a><div class="sub-desc">The mapping is a number indicating the Array index
254 of the field's value. Defaults to the field specification's Array position.</div></li>
258 <p>If a more complex value extraction strategy is required, then configure the Field with a <a href="Ext.data.Field.html#convert" rel="Ext.data.Field#convert" class="docClass">convert</a>
259 function. This is passed the whole row object, and may interrogate it in whatever way is necessary in order to
260 return the desired data.</p>
262 </div></div></div><div id="config-name" class="member ni"><a href="Ext.data.Field.html#config-name" rel="config-name" class="expand more ar"><span> </span></a><div class="title"><div class="meta"><a href="Ext.data.Field.html" class="definedIn docClass">Ext.data.Field</a><br/><a href="../source/Field3.html#Ext-data.Field-cfg-name" class="viewSource">view source</a></div><a name="name"></a><a name="config-name"></a><a href="Ext.data.Field.html#" rel="config-name" class="cls expand">name</a><span> : String</span></div><div class="description"><div class="short">The name by which the field is referenced within the Model. This is referenced by, for example,
263 the dataIndex propert...</div><div class="long"><p>The name by which the field is referenced within the Model. This is referenced by, for example,
264 the <code>dataIndex</code> property in column definition objects passed to <a href="Ext.grid.property.HeaderContainer.html" rel="Ext.grid.property.HeaderContainer" class="docClass">Ext.grid.property.HeaderContainer</a>.</p>
266 <p>Note: In the simplest case, if no properties other than <code>name</code> are required, a field
267 definition may consist of just a String for the field name.</p>
269 </div></div></div><div id="config-persist" class="member ni"><a href="Ext.data.Field.html#config-persist" rel="config-persist" class="expand more ar"><span> </span></a><div class="title"><div class="meta"><a href="Ext.data.Field.html" class="definedIn docClass">Ext.data.Field</a><br/><a href="../source/Field3.html#Ext-data.Field-cfg-persist" class="viewSource">view source</a></div><a name="persist"></a><a name="config-persist"></a><a href="Ext.data.Field.html#" rel="config-persist" class="cls expand">persist</a><span> : Boolean</span></div><div class="description"><div class="short">False to exclude this field from the Ext.data.Model.modified fields in a model. This
270 will also exclude the field from...</div><div class="long"><p>False to exclude this field from the <a href="Ext.data.Model.html#modified" rel="Ext.data.Model#modified" class="docClass">Ext.data.Model.modified</a> fields in a model. This
271 will also exclude the field from being written using a <a href="Ext.data.writer.Writer.html" rel="Ext.data.writer.Writer" class="docClass">Ext.data.writer.Writer</a>. This option
272 is useful when model fields are used to keep state on the client but do not need to be persisted
273 to the server. Defaults to <tt>true</tt>.</p>
274 </div></div></div><div id="config-sortDir" class="member ni"><a href="Ext.data.Field.html#config-sortDir" rel="config-sortDir" class="expand more"><span> </span></a><div class="title"><div class="meta"><a href="Ext.data.Field.html" class="definedIn docClass">Ext.data.Field</a><br/><a href="../source/Field3.html#Ext-data.Field-cfg-sortDir" class="viewSource">view source</a></div><a name="sortDir"></a><a name="config-sortDir"></a><a href="Ext.data.Field.html#" rel="config-sortDir" class="cls expand">sortDir</a><span> : String</span></div><div class="description"><div class="short"><p>(Optional) Initial direction to sort (<code>"ASC"</code> or <code>"DESC"</code>). Defaults to
275 <code>"ASC"</code>.</p>
276 </div><div class="long"><p>(Optional) Initial direction to sort (<code>"ASC"</code> or <code>"DESC"</code>). Defaults to
277 <code>"ASC"</code>.</p>
278 </div></div></div><div id="config-sortType" class="member ni"><a href="Ext.data.Field.html#config-sortType" rel="config-sortType" class="expand more ar"><span> </span></a><div class="title"><div class="meta"><a href="Ext.data.Field.html" class="definedIn docClass">Ext.data.Field</a><br/><a href="../source/Field3.html#Ext-data.Field-cfg-sortType" class="viewSource">view source</a></div><a name="sortType"></a><a name="config-sortType"></a><a href="Ext.data.Field.html#" rel="config-sortType" class="cls expand">sortType</a><span> : Function</span></div><div class="description"><div class="short">(Optional) A function which converts a Field's value to a comparable value in order to ensure
279 correct sort ordering. ...</div><div class="long"><p>(Optional) A function which converts a Field's value to a comparable value in order to ensure
280 correct sort ordering. Predefined functions are provided in <a href="Ext.data.SortTypes.html" rel="Ext.data.SortTypes" class="docClass">Ext.data.SortTypes</a>. A custom
283 <pre><code>// current sort after sort we want
284 // +-+------+ +-+------+
285 // |1|First | |1|First |
286 // |2|Last | |3|Second|
287 // |3|Second| |2|Last |
288 // +-+------+ +-+------+
290 sortType: function(value) {
291 switch (value.toLowerCase()) // native toLowerCase():
293 case 'first': return 1;
294 case 'second': return 2;
300 </div></div></div><div id="config-type" class="member ni"><a href="Ext.data.Field.html#config-type" rel="config-type" class="expand more ar"><span> </span></a><div class="title"><div class="meta"><a href="Ext.data.Field.html" class="definedIn docClass">Ext.data.Field</a><br/><a href="../source/Field3.html#Ext-data.Field-cfg-type" class="viewSource">view source</a></div><a name="type"></a><a name="config-type"></a><a href="Ext.data.Field.html#" rel="config-type" class="cls expand">type</a><span> : Mixed</span></div><div class="description"><div class="short">(Optional) The data type for automatic conversion from received data to the stored value if convert
301 has not been spec...</div><div class="long"><p>(Optional) The data type for automatic conversion from received data to the <i>stored</i> value if <code><a href="Ext.data.Field.html#convert" rel="Ext.data.Field#convert" class="docClass">convert</a></code>
302 has not been specified. This may be specified as a string value. Possible values are</p>
304 <div class="mdetail-params"><ul>
305 <li>auto (Default, implies no conversion)</li>
310 <li>date</li></ul></div>
313 <p>This may also be specified by referencing a member of the <a href="Ext.data.Types.html" rel="Ext.data.Types" class="docClass">Ext.data.Types</a> class.</p>
316 <p>Developers may create their own application-specific data types by defining new members of the
317 <a href="Ext.data.Types.html" rel="Ext.data.Types" class="docClass">Ext.data.Types</a> class.</p>
319 </div></div></div><div id="config-useNull" class="member ni"><a href="Ext.data.Field.html#config-useNull" rel="config-useNull" class="expand more ar"><span> </span></a><div class="title"><div class="meta"><a href="Ext.data.Field.html" class="definedIn docClass">Ext.data.Field</a><br/><a href="../source/Field3.html#Ext-data.Field-cfg-useNull" class="viewSource">view source</a></div><a name="useNull"></a><a name="config-useNull"></a><a href="Ext.data.Field.html#" rel="config-useNull" class="cls expand">useNull</a><span> : Boolean</span></div><div class="description"><div class="short">(Optional) Use when converting received data into a Number type (either int or float). If the value cannot be parsed,...</div><div class="long"><p>(Optional) Use when converting received data into a Number type (either int or float). If the value cannot be parsed,
320 null will be used if useNull is true, otherwise the value will be 0. Defaults to <tt>false</tt>
322 </div></div></div></div></div></div></div><div id="pageContent"></div></div></div></div></body></html>