string som kun acceptere numre?

DU henter vel bare delstrengen ud og laver en Int32.TryParse. Kaster den en exception så ved du at du har fat i noget ulovligt.

TryParse kaster en exception, som du kan fange. Du ved at der er sket en fejl hvis exceptionen bliver fanget. Når dette sker kan du jo reagere udfra dette.

Hvis du er lidt grøn til programmering, så vil jeg råde dig til at læse lidt op på exceptionshåndtering. Der findes nok en artikel eller to på nettet som kan forklare dig hvordan du fanger en.

Kode 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace MCQuai
{
    class CmdMaximit : Command
    {
        public override string name { get { return "maxlimit"; } }
		//public CmdMaxLimit() { }
        public override void Use(Player p,string message)
        {
            if (message == "") { Help(p); return; }
            int number = message.Split(' ').Length;
            if (number > 2) { Help(p); return; }
            if (number == 2)
            {
                int pos = message.IndexOf(' ');
                string t = message.Substring(0, pos).ToLower();
                string s = message.Substring(pos + 1).ToLower();
                int sint;

                if (t == "admin") { if (int.TryParse(s, out sint) == true) Server.maxAdmin = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxAdmin + " for Admins."); }
                else if (t == "mod") { if (int.TryParse(s, out sint) == true) Server.maxMod = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxOp + " for Moderators."); }
                else if (t == "moderator") { if (int.TryParse(s, out sint) == true) Server.maxMod = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxOp + " for Moderators."); }
                else if (t == "op") { if (int.TryParse(s, out sint) == true) Server.maxOp = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxMod + " for Operators."); }
                else if (t == "operator") { if (int.TryParse(s, out sint) == true) Server.maxOp = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxMod + " for Operators."); }
                else if (t == "adv") { if (int.TryParse(s, out sint) == true) Server.maxAdv = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxAdv + " for Advanced Builders."); }
                else if (t == "advbuilder") { if (int.TryParse(s, out sint) == true) Server.maxAdv = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxAdv + " for Advanced Builders."); }
                else if (t == "builder") { if (int.TryParse(s, out sint) == true) Server.maxBuild = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxBuild + " for Builders."); }
                else { Help(p); return; }
            }
        }
        public override void Help(Player p)
        {
            p.SendMessage("/maxlimit or /ml <rank> <number> - Sets the cuboid/replace limit.");
        }
    }
}

Kode 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace MCQuai
{
    class CmdMaxLimit : Command
    {
        public override string name { get { return "maxlimit"; } }
		public CmdMaxLimit() { }
        public override void Use(Player p,string message)
        {
            if (message == "") { Help(p); return; }
            int number = message.Split(' ').Length;
            if (number > 2) { Help(p); return; }
            if (number == 2)
            {
                int pos = message.IndexOf(' ');
                string t = message.Substring(0, pos).ToLower();
                string s = message.Substring(pos + 1).ToLower();
                int sint;

                if (t == "admin") { if (int.TryParse(s, out sint) == true) Server.maxAdmin = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxAdmin + " for Admins."); }
                else if (t == "op") { if (int.TryParse(s, out sint) == true) Server.maxOp = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxMod + " for Operators."); }
                else if (t == "operator") { if (int.TryParse(s, out sint) == true) Server.maxOp = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxMod + " for Operators."); }
                else if (t == "mod") { if (int.TryParse(s, out sint) == true) Server.maxMod = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxOp + " for Moderators."); }
                else if (t == "moderator") { if (int.TryParse(s, out sint) == true) Server.maxMod = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxOp + " for Moderators."); }
                else if (t == "adv") { if (int.TryParse(s, out sint) == true) Server.maxAdv = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxAdv + " for Advanced Builders."); }
                else if (t == "advbuilder") { if (int.TryParse(s, out sint) == true) Server.maxAdv = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxAdv + " for Advanced Builders."); }
                else if (t == "builder") { if (int.TryParse(s, out sint) == true) Server.maxBuild = sint; Player.GlobalMessage("Cuboid/replace limit has been changed to " + Server.maxBuild + " for Builders."); }
                else { Help(p); return; }
            }
        }
        public override void Help(Player p)
        {
            p.SendMessage("/maxlimit or /ml <rank> <number> - Sets the cuboid/replace limit.");
        }
    }
}

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