using static System.Console;
public class Program {
public static void Main() {
var larguraText = "2.00";
var alturaText = "1.00";
var percText = "30";
var total = 0.0;
if (double.TryParse(larguraText, out var largura) && double.TryParse(alturaText, out var altura) && double.TryParse(percText, out var perc)) {
total = largura * altura * (perc / 100);
}
var totalText = total.ToString(); //só para fins didáticos do exemplo
WriteLine(totalText);
}
}
//https://pt.stackoverflow.com/q/320182/101
dXNpbmcgc3RhdGljIFN5c3RlbS5Db25zb2xlOwoJCnB1YmxpYyBjbGFzcyBQcm9ncmFtIHsKCXB1YmxpYyBzdGF0aWMgdm9pZCBNYWluKCkgewoJCXZhciBsYXJndXJhVGV4dCA9ICIyLjAwIjsKCQl2YXIgYWx0dXJhVGV4dCA9ICIxLjAwIjsKCQl2YXIgcGVyY1RleHQgPSAiMzAiOwoJCXZhciB0b3RhbCA9IDAuMDsKCQlpZiAoZG91YmxlLlRyeVBhcnNlKGxhcmd1cmFUZXh0LCBvdXQgdmFyIGxhcmd1cmEpICYmIGRvdWJsZS5UcnlQYXJzZShhbHR1cmFUZXh0LCBvdXQgdmFyIGFsdHVyYSkgJiYgZG91YmxlLlRyeVBhcnNlKHBlcmNUZXh0LCBvdXQgdmFyIHBlcmMpKSB7CgkJCXRvdGFsID0gbGFyZ3VyYSAqIGFsdHVyYSAqIChwZXJjIC8gMTAwKTsKCQl9CgkJdmFyIHRvdGFsVGV4dCA9IHRvdGFsLlRvU3RyaW5nKCk7IC8vc8OzIHBhcmEgZmlucyBkaWTDoXRpY29zIGRvIGV4ZW1wbG8KCQlXcml0ZUxpbmUodG90YWxUZXh0KTsKCX0KfQoKLy9odHRwczovL3B0LnN0YWNrb3ZlcmZsb3cuY29tL3EvMzIwMTgyLzEwMQ==