我们如何在 XSD 中定义任何函数或任何可能的逻辑？ 需要在 XSD 中验证 XML 文件的可能性

Question

Sample XSD file for reference

I want to know whether can we define any function or any encryption/decryption logic in xsd or list of what special features xsd can support?

<?xml version="1.0" encoding="utf-8" ?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema">
<xs:element name="Customer">
<xs:complexType>
<xs:sequence>
<xs:element name="name" type="xs:string" minOccurs="0" />
<xs:element name="address" type="xs:string" minOccurs="0" />
</xs:sequence>
</xs:complexType>
</xs:element>
</xs:schema>

Answer 1

No, this is not possible. XML schema is declarative and doesn't provide a facility to specify imperative logic or what most people would recognise as "code". The set of features provided by XML schema is best summarised by its specification

Answer 2

You haven't stated your actual requirement (what is the validation rule you want to impose?). XSD 1.1 allows you to define assertions using XPath, including the full XPath function library; and a particular implementation of XSD 1.1 may allow those XPath expressions to call out to extensions written in a procedural language like Java.

So if you're using pure XSD 1.0 then the answer is no, but if you're prepared to adopt a solution that only works with Saxon (say), then the answer becomes yes.