C#數學運算運算式解譯器

標籤：c#   數學   運算   運算式   解譯器   

C#數學運算運算式解譯器

測試檔案內容：

a=2+3*2;b=2*(2+3);

瀏覽按鈕事件處理常式：

        private void button_browse_Click(object sender, EventArgs e)        {            OpenFileDialog fbd = new OpenFileDialog();            fbd.Title = "請選擇一個檔案：";            fbd.CheckFileExists = true;            fbd.CheckPathExists = true;            fbd.Filter = "*.txt(文字檔)|*.txt|*.*(所有檔案)|*.*";            fbd.FileName = Environment.GetFolderPath(Environment.SpecialFolder.MyComputer);            if (fbd.ShowDialog() == System.Windows.Forms.DialogResult.OK)            {                textBox_saveDir.Text = fbd.FileName;                try                {                    FileStream fs = new FileStream(fbd.FileName, FileMode.Open, FileAccess.Read);                    StreamReader sr = new StreamReader(fs);                    while (!sr.EndOfStream)                    {                        string line = sr.ReadLine();                        analyse(line);                    }                }                catch (Exception ex)                {                    MessageBox.Show("錯誤：" + ex.Message + "\r\n堆棧：" + ex.StackTrace);                }            }        }

分析一行運算式：

        private void analyse(string line)        {            //以分號作為結束符，支援一行內寫多個語句            string[] expA = line.Split(new string[] { ";" }, StringSplitOptions.RemoveEmptyEntries);            for (int i = 0; i < expA.Length; i++)            {                analyseExpA(expA[i]);            }        }

計算一條運算式：

        private void analyseExpA(string expA)        {            string[] expB = expA.Split(new string[] { "=" }, StringSplitOptions.RemoveEmptyEntries);            for (int i = 0; i < expB.Length; i++ )            {                Regex reg = new Regex("[a-zA-Z]");                if (!reg.IsMatch(expB[i]))                {                    object obj = EvalExpress(expB[i]);                    if (obj != null)                    {                        textBox1.Text += expA + " = " + obj.ToString() + "\r\n";                    }                    else                    {                        textBox1.Text += expA + ",無法識別的運算式\r\n";                    }                }            }        }

源碼下載：C#數學運算運算式解譯器源碼