-<li>date</li></ul></div></div></div></td><td class="msource">Field</td></tr></tbody></table><a id="Ext.data.Field-props"></a><h2>Public Properties</h2><div class="no-members">This class has no public properties.</div><a id="Ext.data.Field-methods"></a><h2>Public Methods</h2><div class="no-members">This class has no public methods.</div><a id="Ext.data.Field-events"></a><h2>Public Events</h2><div class="no-members">This class has no public events.</div></div>
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+<li>date</li></ul></div>
+<p>This may also be specified by referencing a member of the <a href="output/Ext.data.Types.html" ext:cls="Ext.data.Types">Ext.data.Types</a> class.</p>
+<p>Developers may create their own application-specific data types by defining new members of the
+<a href="output/Ext.data.Types.html" ext:cls="Ext.data.Types">Ext.data.Types</a> class.</p></div></div></td><td class="msource">Field</td></tr><tr class="config-row expandable "><td class="micon"><a href="#expand" class="exi"> </a></td><td class="sig"><a id="Ext.data.Field-useNull"></a><b><a href="source/DataField.html#cfg-Ext.data.Field-useNull">useNull</a></b> : Boolean<div class="mdesc"><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,
+null will be used if useNull is true, otherwise the value will be 0. Defaults to <tt>false</tt></div></div></td><td class="msource">Field</td></tr></tbody></table><a id="Ext.data.Field-props"></a><h2>Public Properties</h2><div class="no-members">This class has no public properties.</div><a id="Ext.data.Field-methods"></a><h2>Public Methods</h2><div class="no-members">This class has no public methods.</div><a id="Ext.data.Field-events"></a><h2>Public Events</h2><div class="no-members">This class has no public events.</div></div>
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