这是我的返回，根据网上的方法已经取到了整个返回的数据，但是我只想要customerId的值，请问各位大佬，这该如何取？
{"code":200,"message":"success","body":{"type":"1","role":"1","isTerror":"0","customerId":"I01000007926","name":"王二狗子","identifyTypeCode":"01","identifyTypeName":"居民身份证","identifyNumber":"110101199508151044","addr":"大师傅士大夫士大夫士大夫撒旦","completeAddress":"大师傅士大夫士大夫士大夫撒旦","mobile":"13444455555","specialClient":"00","sex":"2","birthday":"1995-08-15","operateFlag":"Q"}}