C#學習8

C#學習8:建一個WPF文件，實現表達式求值，界面比較簡陋，添加了一張背景圖片，添加背景圖片的代碼是

[csharp] 
<Grid.Background> 
            <ImageBrush ImageSource="/表達式求值;component/Images/1.jpg" /> 
        </Grid.Background> 
再修改background的屬性即可

輸入的表達式形如：((1+2)*5+1)/4=

[csharp] 
using System; 
using System.Collections.Generic; 
using System.Linq; 
using System.Text; 
using System.Windows; 
using System.Windows.Controls; 
using System.Windows.Data; 
using System.Windows.Documents; 
using System.Windows.Input; 
using System.Windows.Media; 
using System.Windows.Media.Imaging; 
using System.Windows.Navigation; 
using System.Windows.Shapes; 
namespace 表達式求值 
{ 
    /// <summary> 
    /// MainWindow.xaml 的交互邏輯 
    /// </summary> 
    public partial class MainWindow : Window 
    { 
        int[,] map = new int[7, 7] {  {1,1,-1,-1,-1,1,1},    // 算符間的優先關系 
                                      {1,1,-1,-1,-1,1,1},   
                                      {1,1,1,1,-1,1,1},   
                                      {1,1,1,1,-1,1,1},   
                                      {-1,-1,-1,-1,-1,0,100},   
                                      {1,1,1,1,100,1,1},   
                                      {-1,-1,-1,-1,-1,100,0}   
                                   }; 
        char[]str=new char[1005]; 
        char[]optr = new char[1005]; 
        double[]opnd = new double[1005]; 
        int t1, t2, k, len; 
        char ch, zz; 
        int temp1, temp2; 
        double a, b;   
        public MainWindow() 
        { 
            InitializeComponent(); 
        } 
        public int cam(char c) 
        { 
            switch (c) 
            { 
                case '+': return 0; 
                case '-': return 1; 
                case '*': return 2; 
                case '/': return 3; 
                case '(': return 4; 
                case ')': return 5; 
                case '#': return 6; 
                default: return -1; 
            } 
        } 
        public double sol(double x, char c, double y) 
        { 
            switch (c) 
            { 
                case '+': return x + y; 
                case '-': return x - y; 
                case '*': return x * y; 
                case '/': return x / y; 
                default: return -1; 
            } 
        } 
        public int z(char c) 
        { 
            if ('0' <= c && c <= '9' || c == '.') 
                return 1; 
            if (c == ' ') 
                return -1; 
            return 0; 
        }   
        private void button2_Click(object sender, RoutedEventArgs e) 
        { 
            this.Close(); 
        } 
        private void button1_Click(object sender, RoutedEventArgs e) 
        { 
            string s = resource.Text; 
            str = s.ToCharArray(); 
            len = s.Length; 
            str[len - 1] = '#'; //處理等於號   
            t1 = t2 = k = 0; 
            optr[t1++] = '#'; 
            ch = str[k++]; 
            while (ch != '#' || optr[t1 - 1] != '#') 
            { 
                if (z(ch) == 1)  //操作數入棧   
                { 
                    double num1,num2,sm; 
                    int t,flagg; 
                    num1=num2=0; 
                    t=k-1; 
                    flagg=0; 
                    sm=0.1; 
                    while (z(str[t]) == 1) 
                    { 
                        if (str[t] == '.') 
                        { 
                            flagg = 1; 
                            t++; 
                            continue; 
                        } 
                        if (flagg == 0) 
                            num1 = num1 * 10 + (str[t] - '0'); 
                        else 
                        { 
                            num2 += sm * (str[t] - '0'); 
                            sm *= 0.1; 
                        } 
                        t++; 
                    } 
                    opnd[t2++] =num1+num2; //把字符串轉換成浮點數 
                    k = t; 
                    ch = str[k++]; 
                } 
                else if (z(ch) == -1) 
                    ch = str[k++]; 
                else 
                { 
                    temp1 = cam(optr[t1 - 1]); 
                    temp2 = cam(ch); 
                    if (map[temp1,temp2] == -1)  //棧頂元素優先權低   
                    { 
                        optr[t1++] = ch; 
                        ch = str[k++]; 
                    } 
                    else if (map[temp1,temp2] == 0) //脫括號並接受下一個字符   
                    { 
                        t1--; 
                        ch = str[k++]; 
                    } 
                    else    //退棧並將運算結果   
                    { 
                        zz = optr[--t1]; 
                        a = opnd[--t2]; 
                        b = opnd[--t2]; 
                        opnd[t2++] = sol(b, zz, a); 
                    } 
                }   
            } 
            result.Text = opnd[0].ToString(); 
        } 
    } 
}