dart remove last character from string

public static String removeLastCharacter(String str) {   
	String result = null;   
    if ((str != null) && (str.length() > 0)) {      
    	result = str.substring(0, str.length() - 1);   
    }   
    
    return result;
}

String loginToken="[wdsd34svdf]";
System.out.println(loginToken.substring(1, loginToken.length()-1));