C#作业——表达式计算器+小数点

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace WindowsFormsApplication2
{
public partial class Form1 : Form
{
public String expression;
public Form1()
{
InitializeComponent();
}

private void textBox1_TextChanged(object sender, EventArgs e)
{
expression = textBox1.Text;
}

private void button1_Click(object sender, EventArgs e)
{
textBox1.Text = expression + "=" + Result(expression);
}
private double Result(String expression)
{
int length = expression.Length;
char[] a = expression.ToCharArray(0, length);
double[] data = new double[10];
char[] oper = new char[10];
int datacount = 0, opercount = 0;
double temp = 0;
int dicimal = -1;
double tempdi=1;
for (int m = 0; m < length; m++)
{

if (Char.IsDigit(a[m]) == true)
{

if (dicimal == -1)
{
temp *= 10;
temp += a[m] - '0';
}
else
{
dicimal++;
for (int q = 0; q < dicimal; q++)
tempdi = tempdi * 0.1;
temp = temp + (a[m] - '0') * tempdi;

}

}
else if (a[m] == '.')
{
dicimal = 0;
}
else
{
dicimal = -1;
tempdi = 1;
data[datacount] = temp;
datacount++;
temp = 0;
oper[opercount] = a[m];
opercount++;
}
}

data[datacount] = temp;
datacount++;

int temp1 = 0;
int tempdata = 0;
while (temp1 < opercount)
{
double para1 = data[tempdata];
tempdata++;
double para2 = data[tempdata];
if (oper[temp1] == '+')
{ data[tempdata] = para1 + para2; }
else if (oper[temp1] == '-')
{ data[tempdata] = para1 - para2; }
else if (oper[temp1] == '*')
{ data[tempdata] = para1 * para2; }
else if (oper[temp1] == '/')
{ data[tempdata] = para1 / para2; }
temp1++;

}

return data[tempdata];

}
}
}