type Cookie struct {
    Name string
    Value string

    Path    string  // optional
    Domain   string  // optional
    Expires  time.Time // optional
    RawExpires string  // for reading cookies only

    // MaxAge=0 means no 'Max-Age' attribute specified.
    // MaxAge<0 means delete cookie now, equivalently 'Max-Age: 0'
    // MaxAge>0 means Max-Age attribute present and given in seconds
    MaxAge  int
    Secure  bool
    HttpOnly bool
    Raw   string
    Unparsed []string // Raw text of unparsed attribute-value pairs
}

COOKIE_MAX_MAX_AGE   = time.Hour * 24 / time.Second  // 单位：秒。
maxAge = int(COOKIE_MAX_MAX_AGE)
uid:="10"

uid_cookie:=&http.Cookie{
    Name:  "uid",
    Value:  uid,
    Path:   "/",
    HttpOnly: false,
    MaxAge:  maxAge
  }

http.SetCookie(c.Writer,uid_cookie)

var c = *gin.Context
uid, err := c.Request.Cookie("uid")