王新阳

来源：https://www.jianshu.com/p/85855a991275

方法一：添加自定义header，缺点是不支持正则，只能设置一个网站，或者*对全部网站开放

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <system.webServer>
	<httpProtocol>
	  <customHeaders>
		   <add name="Access-Control-Allow-Origin" value="https://www.domain1.com" />
	  </customHeaders>
	</httpProtocol>
    </system.webServer>
</configuration>

方法二：使用正则，可添加多个，需要安装微软的URL Rewrite组件

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <system.webServer>
	<rewrite>
		<outboundRules>
			<rule name="AddCrossDomain">
				<match serverVariable="RESPONSE_Access_Control_Allow_Origin" pattern=".*" />
				<conditions logicalGrouping="MatchAll" trackAllCaptures="true">
					<add input="{HTTP_ORIGIN}" pattern="(https?://((www\.)?domain1\.com|(www\.)?domain2\.cn))" />
				</conditions>
				<action type="Rewrite" value="{C:0}" />
			</rule>
		</outboundRules>
        </rewrite>
    </system.webServer>
</configuration>