WF4学习-24点游戏

目标：用WF+WPF完成24点游戏程序。

1.界面，新建一个WPF项目，4个Label+2个按钮，注意：4个Label分别设置Tag值为：0~3

<Window x:Class="Point24.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="24点游戏" Height="204" Width="394" FontSize="12" ResizeMode="NoResize" WindowStartupLocation="CenterScreen">
    <Grid Name="gridMain">
        <Label Content="0" Height="93" HorizontalAlignment="Left" Margin="12,12,0,0" Name="lblNum1" VerticalAlignment="Top" Width="82" FontSize="60" HorizontalContentAlignment="Center" VerticalContentAlignment="Center" Tag="0" />
        <Label Content="0" FontSize="60" Height="93" HorizontalAlignment="Left" HorizontalContentAlignment="Center" Margin="100,12,0,0" Name="lblNum2" VerticalAlignment="Top" VerticalContentAlignment="Center" Width="82" Tag="1" />
        <Label Content="0" FontSize="60" Height="93" HorizontalAlignment="Left" HorizontalContentAlignment="Center" Margin="188,12,0,0" Name="lblNum3" VerticalAlignment="Top" VerticalContentAlignment="Center" Width="82" Tag="2" />
        <Label Content="0" FontSize="60" Height="93" HorizontalAlignment="Left" HorizontalContentAlignment="Center" Margin="276,12,0,0" Name="lblNum4" VerticalAlignment="Top" VerticalContentAlignment="Center" Width="82" Tag="3" />
        <Button Content="New _Game" Height="23" HorizontalAlignment="Left" Margin="71,130,0,0" Name="btnNewGame" VerticalAlignment="Top" Width="100" FontSize="12" Click="btnNewGame_Click" />
        <Button Content="Auto Calculate" FontSize="12" Height="23" HorizontalAlignment="Left" Margin="197,130,0,0" Name="btnCalculate" VerticalAlignment="Top" Width="100" Click="btnCalculate_Click" />
    </Grid>
</Window>

2.创建“自动生成随机数的活动”，新建项->Workflow->活动，名称：CreateRandomNumberActivity.xaml

活动输入：无
活动输出：4个随机数，这里用List<int>集合

3.创建“自动计算的活动”，新建项->Workflow->代码活动，名称：CalculateActivity.cs

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

namespace Point24 {

    public sealed class CalculateActivity : CodeActivity {

        public InArgument<List<int>> Nums { get; set; }
        public OutArgument<string> Result { get; set; }

        protected override void Execute(CodeActivityContext context) {
            List<int> nums = context.GetValue(Nums);
            string result=string.Empty;
            if (!Calculate(nums, ref result)) {
                result = "此题无解";
            }
            context.SetValue(Result, result);
        }

        private bool Calculate(List<int> nums, ref string result) {
            DataTable dt = new DataTable();
            string[] opts = { "+", "-", "*", "/" };

            for (int a = 0; a < 4; a++) {
                for (int b = 0; b < 4; b++) {
                    if (a == b) continue;
                    for (int c = 0; c < 4; c++) {
                        if (a == c || b == c) continue;
                        for (int d = 0; d < 4; d++) {
                            if (a == d || b == d || c == d) continue;
                            for (int e = 0; e < 4; e++) {
                                for (int f = 0; f < 4; f++) {
                                    for (int g = 0; g < 4; g++) {
                                        try {
                                            string strExpression = string.Format("(({0}{4}{1}){5}{2}){6}{3}",
                                                                                nums[a], nums[b], nums[c], nums[d],
                                                                                opts[e], opts[f], opts[g]);
                                            double r = Convert.ToDouble(dt.Compute(strExpression, null));
                                            if (r == 24.0) {
                                                result = strExpression;
                                                return true;
                                            }

                                            strExpression = string.Format("({0}{4}{1}){5}({2}{6}{3})",
                                                nums[a], nums[b], nums[c], nums[d],
                                                opts[e], opts[f], opts[g]);
                                            r = Convert.ToDouble(dt.Compute(strExpression, null));
                                            if (r == 24.0) {
                                                result = strExpression;
                                                return true;
                                            }
                                        } catch {}
                                    }
                                }
                            }
                        }
                    }
                }
            }

            return false;
        }
    }
}

活动输入：随机数集合List<int>
活动输出：计算结果String

简单讲解程序：首先创建一个表达式，然后用DataTable.Computer方法计算表达式的值是否是24，最终将结果返回。
其中前4个for用于生成随机数的排列，for中if用以判断一个数字不能重复使用；后面3个for用以生成表达式中任意三个操作符。然后计算：（（数1？数2）？数3）？数4 ，第二种表达式模式是：（数1？数2）？（数3？数4），其中？表示某种操作符。

4.WPF中给按钮添加事件

List<int> nums;
private void btnNewGame_Click(object sender, RoutedEventArgs e) {
    IDictionary<string,object> output = WorkflowInvoker.Invoke(new CreateRandomNumberActivity());
    nums = output["Nums"] as List<int>;

    /*
        * 遍历子控件
        * 注意：
        * 1.设置Grid的Name
        * 2.设置Label的Tag分别为0~3
        */
    int count = VisualTreeHelper.GetChildrenCount(gridMain);
    for (int i = 0; i < count; i++) {
        object ctrl = VisualTreeHelper.GetChild(gridMain, i);
        if (ctrl is Label) {
            Label lbl = ctrl as Label;
            if (lbl.Tag != null) {
                int tag = Convert.ToInt32(lbl.Tag);
                lbl.Content = nums[tag].ToString();
            }
        }
    }
}

private void btnCalculate_Click(object sender, RoutedEventArgs e) {
    IDictionary<string,object> input=new Dictionary<string,object>{
        {"Nums",nums}
    };
    IDictionary<string,object> output = WorkflowInvoker.Invoke(new CalculateActivity(), input);
    string message = output["Result"] as string;
    MessageBox.Show(message);
}

最后看看效果图，还挺智能的！

下载地址：http://u.163.com/48Ozl

提取码：veziqgsa