linux shell中curl 发送post请求json格式问题的处理方法

curl -i -X POST -H 'Content-type':'application/json' -d {"BTime":""$btime""} http://api.baidu.com

atime=`date -d "$1" +%s`
btime=`date -d "$2" +%s`
curl -i -X POST -H "'Content-type':'application/json'" -d '{"ATime":"'$atime'","BTime":"'$btime'"}' $url

curl -i -X POST -H 'Content-type':'application/json' -d '{"keyWord":"雅诗兰黛","page":1,"pageSize":12,"sortFieldList":["isCombo|desc"]}' http://127.0.0.1:8015/search/prod/query
# 注意的是，json数据里变量要用 '' 括起来