C # Learning 8

C # Learning 8: Create a WPF file and evaluate the expression. The interface is simple. Add a background image. The code for adding a background image is

[Csharp]
<Grid. Background>
<ImageBrush ImageSource = "/expression evaluate; component/Images/1.jpg"/>
</Grid. Background>
Modify the attributes of the background.

The input expression is as follows: (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;
Evaluate the namespace expression
{
/// <Summary>
/// Interaction logic of MainWindow. xaml
/// </Summary>
Public partial class MainWindow: Window
{
Int [,] map = new int [7, 7] {,-1,-1,-, 1}, // priority relationship between operators
{1, 1,-1,-1,-1, 1 },
{1, 1, 1,-1, 1 },
{1, 1, 1,-1, 1 },
{-1,-1,-1,-1,-100 },
{, 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 button#click (object sender, RoutedEventArgs e)
{
String s = resource. Text;
Str = s. ToCharArray ();
Len = s. Length;
Str [len-1] = '#'; // process the equals sign
T1 = t2 = k = 0;
Optr [t1 ++] = '#';
Ch = str [k ++];
While (ch! = '#' | Optr [t1-1]! = '#')
{
If (z (ch) = 1) // the operand is added to the stack.
{
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; // converts a string to a floating point number.
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) // The top element of the stack has a low priority.
{
Optr [t1 ++] = ch;
Ch = str [k ++];
}
Else if (map [temp1, temp2] = 0) // parentheses and accept the next character
{
T1 --;
Ch = str [k ++];
}
Else // unstack and calculate the result
{
Zz = optr [-- t1];
A = opnd [-- t2];
B = opnd [-- t2];
Opnd [t2 ++] = sol (B, zz, );
}
}
}
Result. Text = opnd [0]. ToString ();
}
}
}