accept loop param on task

server/ajax/form/form.go

@@ -60,6 +60,11 @@ func ToStrArr(k string) []string {
 	return outArr
 }
 
+func ToDuration(s string) time.Duration {
+	d, _ := time.ParseDuration(s)
+	return d
+}
+
 func ToTime(s string) time.Time {
 	v, err := time.Parse("2006-01-02 15:04:05", s)
 	if err != nil || v.IsZero() {