默认值未设置为预填充

Question

我有以下xsd：

中列出的paymentcard标签示例

<xs:element name="paymentCard" maxOccurs="unbounded">
    <xs:complexType>
        <xs:sequence>
            <xs:element type="cardsTypeRestriction" name="cardType" maxOccurs="1" />
            <xs:element type="xs:string" name="cardHolderName" minOccurs="0" maxOccurs="1"/>
            <xs:element type="xs:string" name="validFrom" minOccurs="0" maxOccurs="1"/>
            <xs:element type="xs:string" name="expirationDate" minOccurs="0" maxOccurs="1"/>
            <xs:element name="cardNumbers" maxOccurs="1">
                <xs:complexType>
                    <xs:sequence>
                        <xs:element type="xs:string" name="cardNumber" maxOccurs="unbounded"/>
                    </xs:sequence>
                </xs:complexType>
            </xs:element>
            <xs:element name="cardCurrencies" maxOccurs="1">
                <xs:complexType>
                    <xs:sequence>
                        <xs:element type="cardsCurrencyRestriction" name="cardCurrency" maxOccurs="unbounded" default="GBP"/>
                    </xs:sequence>
                </xs:complexType>
            </xs:element>
            <xs:element name="cardAmounts" maxOccurs="1">
                <xs:complexType>
                    <xs:sequence>
                        <xs:element type="xs:float" name="cardAmount" maxOccurs="unbounded" default="20.00"/>
                    </xs:sequence>
                </xs:complexType>
            </xs:element>
            <xs:element type="xs:string" name="cardCvv" maxOccurs="1" default="123"/>
            <xs:element type="xs:string" name="cardIssueNumber" minOccurs="0" maxOccurs="1"/>
        </xs:sequence>
    </xs:complexType>
</xs:element>

但是当我从这样的xsd创建xml时，它没有提供任何默认的预填充值，所以我得到了这个xml：

<paymentCard>
    <cardType></cardType>
    <cardNumbers>
         <cardNumber></cardNumber>
    </cardNumbers>
    <cardCurrencies>
         <cardCurrency></cardCurrency>
    </cardCurrencies>
    <cardAmounts>
         <cardAmount></cardAmount>
    </cardAmounts>
    <cardCvv></cardCvv>
</paymentCard>

创建新的xml时我想要的是

<paymentCard>
    <cardType></cardType>
    <cardNumbers>
         <cardNumber></cardNumber>
    </cardNumbers>
    <cardCurrencies>
         <cardCurrency>GBP</cardCurrency>
    </cardCurrencies>
    <cardAmounts>
         <cardAmount>20.00</cardAmount>
    </cardAmounts>
    <cardCvv>123</cardCvv>
</paymentCard>

仅填充cardType和cardNumber。 那可能吗？如果是，我的xsd有什么问题？