"msg": "invalid character '+' lo

近期在使用Postman接口的遇到标题中的报错：
"msg": "invalid character '+' looking for beginning of value"
发现一个小细节，把过程记录在这

实际的接口请求：

{
"base_info":{"type":1},
"contact_info":
    {"phone":"+886-22203678",
    "email":"demo@demo.com"
    },
"media_info":
    {"media_type":1}
}

根据实际的接口参数，在Postman中添加body
body：

{
"base_info":{"type":1},
"contact_info":
    {"phone":{{phone}},
    "email":{{email}}
    },
"media_info":
    {"media_type":1}
}

在pre-request script中创建phone和email变量
pre-request script：

var id_begins_with = 1424000000
var id = Math.floor(Math.random() * 999999) ;

var mix_id = id_begins_with + id
str = mix_id.toString()
// str = '' + mix_id
console.log(str)
var phone = "+886-" + str
var email = str + "@auto.com"

console.log(phone)
console.log(email)

pm.environment.set("id", mix_id);
pm.environment.set("phone", phone);
pm.environment.set("email", email);

发送请求，response body返回报错
response body：

{
    "code": 2,
    "msg": "invalid character '+' looking for beginning of value",
    "data": null
}

在pre-request script中查看phone和email的字符类型：

console.log(typeof phone)
console.log(typeof email)

console中打印出来的phone和email都是符合要求的，字符类型也都为string，不知道为什么传到body后就报错，折腾了很久，才在看request body的时候发现，真实的接口中phone和email都是带引号的，而以上脚本处理后传到body中，两个变量的值都没有引号，解决方法是：在body中给email和phone都加上引号

{
"base_info":{"type":1},
"contact_info":
    {"phone":"{{phone}}",
    "email":"{{email}}"
    },
"media_info":
    {"media_type":1}
}

很神奇的postman，变量可以直接用引号