1、xml

<field name="stores" formElement="multiselect">
            <argument name="data" xsi:type="array">
                <item name="config" xsi:type="array">
                    <item name="source" xsi:type="string">rule</item>
                    <item name="dataType" xsi:type="string">text</item>
                    <item name="visibleValue" xsi:type="string">1</item>
                </item>
            </argument>
            <settings>
                <dataType>text</dataType>
                <label translate="true">选择关联店铺</label>
                <validation>
                    <rule name="required-entry" xsi:type="boolean">true</rule>
                </validation>
            </settings>
            <formElements>
                <multiselect>
                    <settings>
                        <options class="Magento\Store\Model\System\Store"/>
                    </settings>
                </multiselect>
            </formElements>
        </field>