The source code

/** - * @class Ext.data.Field - *

This class encapsulates the field definition information specified in the field definition objects - * passed to {@link Ext.data.Record#create}.

- *

Developers do not need to instantiate this class. Instances are created by {@link Ext.data.Record.create} - * and cached in the {@link Ext.data.Record#fields fields} property of the created Record constructor's prototype.

- */ -Ext.data.Field = Ext.extend(Object, { - - constructor : function(config){ - if(Ext.isString(config)){ - config = {name: config}; - } - Ext.apply(this, config); - - var types = Ext.data.Types, - st = this.sortType, - t; - - if(this.type){ - if(Ext.isString(this.type)){ - this.type = Ext.data.Types[this.type.toUpperCase()] || types.AUTO; - } - }else{ - this.type = types.AUTO; - } - - // named sortTypes are supported, here we look them up - if(Ext.isString(st)){ - this.sortType = Ext.data.SortTypes[st]; - }else if(Ext.isEmpty(st)){ - this.sortType = this.type.sortType; - } - - if(!this.convert){ - this.convert = this.type.convert; - } - }, - -

/** - * @cfg {String} name - * The name by which the field is referenced within the Record. This is referenced by, for example, - * the dataIndex property in column definition objects passed to {@link Ext.grid.ColumnModel}. - *

Note: In the simplest case, if no properties other than name are required, a field - * definition may consist of just a String for the field name.

- */ -

/** - * @cfg {Mixed} type - * (Optional) The data type for automatic conversion from received data to the stored value if {@link Ext.data.Field#convert convert} - * has not been specified. This may be specified as a string value. Possible values are - *

auto (Default, implies no conversion)
string
int
float
boolean
date

- *

This may also be specified by referencing a member of the {@link Ext.data.Types} class.

- *

Developers may create their own application-specific data types by defining new members of the - * {@link Ext.data.Types} class.

- */ -

/** - * @cfg {Function} convert - * (Optional) A function which converts the value provided by the Reader into an object that will be stored - * in the Record. It is passed the following parameters:

v : Mixed
The data value as read by the Reader, if undefined will use - * the configured {@link Ext.data.Field#defaultValue defaultValue}.
rec : Mixed
The data object containing the row as read by the Reader. - * Depending on the Reader type, this could be an Array ({@link Ext.data.ArrayReader ArrayReader}), an object - * ({@link Ext.data.JsonReader JsonReader}), or an XML element ({@link Ext.data.XMLReader XMLReader}).

- *


-// example of convert function
-function fullName(v, record){
-    return record.name.last + ', ' + record.name.first;
-}
-
-function location(v, record){
-    return !record.city ? '' : (record.city + ', ' + record.state);
-}
-
-var Dude = Ext.data.Record.create([
-    {name: 'fullname',  convert: fullName},
-    {name: 'firstname', mapping: 'name.first'},
-    {name: 'lastname',  mapping: 'name.last'},
-    {name: 'city', defaultValue: 'homeless'},
-    'state',
-    {name: 'location',  convert: location}
-]);
-
-// create the data store
-var store = new Ext.data.Store({
-    reader: new Ext.data.JsonReader(
-        {
-            idProperty: 'key',
-            root: 'daRoot',
-            totalProperty: 'total'
-        },
-        Dude  // recordType
-    )
-});
-
-var myData = [
-    { key: 1,
-      name: { first: 'Fat',    last:  'Albert' }
-      // notice no city, state provided in data object
-    },
-    { key: 2,
-      name: { first: 'Barney', last:  'Rubble' },
-      city: 'Bedrock', state: 'Stoneridge'
-    },
-    { key: 3,
-      name: { first: 'Cliff',  last:  'Claven' },
-      city: 'Boston',  state: 'MA'
-    }
-];
-     *

- */ -

/** - * @cfg {String} dateFormat - *

(Optional) Used when converting received data into a Date when the {@link #type} is specified as "date".

- *

A format string for the {@link Date#parseDate Date.parseDate} function, or "timestamp" if the - * value provided by the Reader is a UNIX timestamp, or "time" if the value provided by the Reader is a - * javascript millisecond timestamp. See {@link Date}

- */ - dateFormat: null, - -

/** - * @cfg {Boolean} useNull - *

(Optional) Use when converting received data into a Number type (either int or float). If the value cannot be parsed, - * null will be used if useNull is true, otherwise the value will be 0. Defaults to false - */ - useNull: false, - -

/** - * @cfg {Mixed} defaultValue - * (Optional) The default value used when a Record is being created by a {@link Ext.data.Reader Reader} - * when the item referenced by the {@link Ext.data.Field#mapping mapping} does not exist in the data - * object (i.e. undefined). (defaults to "") - */ - defaultValue: "", -

/** - * @cfg {String/Number} mapping - *

(Optional) A path expression for use by the {@link Ext.data.DataReader} implementation - * that is creating the {@link Ext.data.Record Record} to extract the Field value from the data object. - * If the path expression is the same as the field name, the mapping may be omitted.

- *

The form of the mapping expression depends on the Reader being used.

- *

{@link Ext.data.JsonReader}
The mapping is a string containing the javascript - * 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.
{@link Ext.data.XmlReader}
The mapping is an {@link Ext.DomQuery} path to the data - * item relative to the DOM element that represents the {@link Ext.data.XmlReader#record record}. Defaults to the field name.
{@link Ext.data.ArrayReader}
The mapping is a number indicating the Array index - * of the field's value. Defaults to the field specification's Array position.

- *

If a more complex value extraction strategy is required, then configure the Field with a {@link #convert} - * function. This is passed the whole row object, and may interrogate it in whatever way is necessary in order to - * return the desired data.

- */ - mapping: null, -

/** - * @cfg {Function} sortType - * (Optional) A function which converts a Field's value to a comparable value in order to ensure - * correct sort ordering. Predefined functions are provided in {@link Ext.data.SortTypes}. A custom - * sort example:


-// current sort     after sort we want
-// +-+------+          +-+------+
-// |1|First |          |1|First |
-// |2|Last  |          |3|Second|
-// |3|Second|          |2|Last  |
-// +-+------+          +-+------+
-
-sortType: function(value) {
-   switch (value.toLowerCase()) // native toLowerCase():
-   {
-      case 'first': return 1;
-      case 'second': return 2;
-      default: return 3;
-   }
-}
-     *

- */ - sortType : null, -

/** - * @cfg {String} sortDir - * (Optional) Initial direction to sort ("ASC" or "DESC"). Defaults to - * "ASC". - */ - sortDir : "ASC", -

/** - * @cfg {Boolean} allowBlank - * (Optional) Used for validating a {@link Ext.data.Record record}, defaults to true. - * An empty value here will cause {@link Ext.data.Record}.{@link Ext.data.Record#isValid isValid} - * to evaluate to false. - */ - allowBlank : true -}); -