using static System.Console;
 
public class Program {
	public static void Main() {
	    var texto = "(99) 9999-9999";
		WriteLine(texto.Replace(new string[] {"(", ")", "-", " " }, ""));
	}
}
 
public static class StringExt {
    public static string Replace(this string str, string[] separators, string newValue) {
	    foreach (var chr in separators) str = str.Replace(chr, newValue);
		return str;
	}
}
 
//https://pt.stackoverflow.com/q/98332/101

dXNpbmcgc3RhdGljIFN5c3RlbS5Db25zb2xlOwoJCQkJCQpwdWJsaWMgY2xhc3MgUHJvZ3JhbSB7CglwdWJsaWMgc3RhdGljIHZvaWQgTWFpbigpIHsKCSAgICB2YXIgdGV4dG8gPSAiKDk5KSA5OTk5LTk5OTkiOwoJCVdyaXRlTGluZSh0ZXh0by5SZXBsYWNlKG5ldyBzdHJpbmdbXSB7IigiLCAiKSIsICItIiwgIiAiIH0sICIiKSk7Cgl9Cn0KCnB1YmxpYyBzdGF0aWMgY2xhc3MgU3RyaW5nRXh0IHsKICAgIHB1YmxpYyBzdGF0aWMgc3RyaW5nIFJlcGxhY2UodGhpcyBzdHJpbmcgc3RyLCBzdHJpbmdbXSBzZXBhcmF0b3JzLCBzdHJpbmcgbmV3VmFsdWUpIHsKCSAgICBmb3JlYWNoICh2YXIgY2hyIGluIHNlcGFyYXRvcnMpIHN0ciA9IHN0ci5SZXBsYWNlKGNociwgbmV3VmFsdWUpOwoJCXJldHVybiBzdHI7Cgl9Cn0KCi8vaHR0cHM6Ly9wdC5zdGFja292ZXJmbG93LmNvbS9xLzk4MzMyLzEwMQ==