SMART datagrid v.1 > Classes > DataSet
Return DataField object which is corresponding to parameter field.
If field is string, it will compare with field name to find it, and if it is number, it will return the field of the corresponding location. If ignoreCase is true, it will not be case sensitive. If no corresponding field, it will return null.
var field = dataset.getFieldIndexEx('quantity');
field.setDatetimeFormat('yyyy-MM-dd');