<form method="POST" enctype="multipart/form-data" action="mygo">
 <input type=hidden name="emails[]" value="email1@email.com">
 <input type=hidden name="emails[]" value="email2@email.com">
 <input type=hidden name="emails[]" value="email3@email.com">
</form>

<form method="POST" enctype="multipart/form-data" action="mygo">
 <input type=hidden name="emails" value="email1@email.com">
 <input type=hidden name="emails" value="email2@email.com">
 <input type=hidden name="emails" value="email3@email.com">
</form>

func main() {
// ...
    router.POST("mygo",parseFunc)
}

func mygo(c *gin.Context) {
  c.Request.ParseForm()
  log.Printf("%v",c.Request.PostForm["emails"]) // ""
  log.Printf("%v",c.PostForm("emails") // "email3@email.com"
}

<form method="POST" enctype="multipart/form-data" action="mygo">
 <input type=hidden name="emails" value="email1@email.com">
 <input type=hidden name="emails" value="email2@email.com">
 <input type=hidden name="emails" value="email3@email.com">
</form>

r.POST("/", func(c *gin.Context) {
        c.Request.ParseMultipartForm(1000)
        for key, value := range c.Request.PostForm {
            fmt.Println(key,value)
        }
    })

<form method="POST" action="mygo">
     <input type=hidden name="emails" value="email1@email.com">
     <input type=hidden name="emails" value="email2@email.com">
     <input type=hidden name="emails" value="email3@email.com">
    </form>

 r.POST("/", func(c *gin.Context) {
            c.Request.ParseForm()
            for key, value := range c.Request.PostForm {
                fmt.Println(key,value)
            }
        })

emails [email1@email.com email2@email.com email3@email.com]

emails := c.PostFormArray("emails")