关于extjs field的校验

最近项目需要用到对输入字段进行校验，翻看了EXTJS TextField的联机文档，里面有如下说明：

Validates a value according to the field's validation rules and marks the field as invalid
     * if the validation fails. Validation rules are processed in the following order:
     * 

     * 
     * 
1. Field specific validator
     * 

     * 
A validator offers a way to customize and reuse a validation specification.
     * If a field is configured with a {@link #validator}
     * function, it will be passed the current field value.  The {@link #validator}
     * function is expected to return either:
     * 

     * 
Boolean true if the value is valid (validation continues).
     * 
a String to represent the invalid message if invalid (validation halts).
     * 

     * 

     * 
     * 
2. Basic Validation
     * 

     * 
If the {@link #validator} has not halted validation,
     * basic validation proceeds as follows:
     * 
     * 

     * 
     * 
{@link #allowBlank} : (Invalid message =
     * {@link #emptyText})

     * Depending on the configuration of {@link #allowBlank}, a
     * blank field will cause validation to halt at this step and return
     * Boolean true or false accordingly.  
     * 
     * 
     * 
{@link #minLength} : (Invalid message =
     * {@link #minLengthText})

     * If the passed value does not satisfy the {@link #minLength}
     * specified, validation halts.
     * 
     * 
     * 
{@link #maxLength} : (Invalid message =
     * {@link #maxLengthText})

     * If the passed value does not satisfy the {@link #maxLength}
     * specified, validation halts.
     * 
     * 
     * 

     * 

     * 
     * 
3. Preconfigured Validation Types (VTypes)
     * 

     * 
If none of the prior validation steps halts validation, a field
     * configured with a {@link #vtype} will utilize the
     * corresponding {@link Ext.form.VTypes VTypes} validation function.
     * If invalid, either the field's {@link #vtypeText} or
     * the VTypes vtype Text property will be used for the invalid message.
     * Keystrokes on the field will be filtered according to the VTypes
     * vtype Mask property.
     * 

     * 
     * 
4. Field specific regex test
     * 

     * 
If none of the prior validation steps halts validation, a field's
     * configured {@link #regex} test will be processed.
     * The invalid message for this test is configured with
     * {@link #regexText}.
     * 

     * 
     * @param {Mixed} value The value to validate
     * @return {Boolean} True if the value is valid, else false
     */