string.go
func StringMarshalJSON(data interface{}, indent string) string {
	buffer, err := json.MarshalIndent(data, "", indent)
	if err != nil {
		return ""
	}
	return string(buffer)
}
func StringMarshalJSON(data interface{}, indent string) string {
	buffer, err := json.MarshalIndent(data, "", indent)
	if err != nil {
		return ""
	}
	return string(buffer)
}
func StringMarshalJSON ( data interface { } , indent string ) string { buffer , err := json . MarshalIndent ( data , " " , indent ) if err != nil { return " " } return string ( buffer ) }
// StringMarshalJSON marshals data to an indented string.
StringMarshalJSON marshals data to an indented string .