一、前言
Hello，又见面了，今天分享如何使用Unity制作计算器，难度中等，可以用来学习，或者当成其他项目的小组件导入。
当然，也可以导出来，发布到网页端，来做一个嵌入式工具也可以。
二、效果图及源工程
效果图：
源工程： https://wwr.lanzoui.com/iHOuzpo4lti
三、实现
3-1 界面搭建
所有的按钮摆放到Background下面。
3-2 代码实现
首先找到所有的按钮，添加到事件：
代码语言：javascript复制 //结果显示
TextComputeProcess = GameObject.Find("Canvas/Background/Image/TextComputeProcess").GetComponent<Text>();
TextComputeResult = GameObject.Find("Canvas/Background/Image/TextComputeResult").GetComponent<Text>();
TextComputeResult.text = "0";
RUNSTATE = 0;
//操作
BtnReset = GameObject.Find("Canvas/Background/重置").GetComponent<Button>();
BtnReset.onClick.AddListener(() => OperationDispose("CE"));
BtnDelete = GameObject.Find("Canvas/Background/删除").GetComponent<Button>();
BtnDelete.onClick.AddListener(() => OperationDispose("Del"));
//加减乘除
BtnAdd = GameObject.Find("Canvas/Background/加").GetComponent<Button>();
BtnAdd.onClick.AddListener(() => OperationDispose(" "));
BtnSub = GameObject.Find("Canvas/Background/减").GetComponent<Button>();
BtnSub.onClick.AddListener(() => OperationDispose("-"));
BtnMul = GameObject.Find("Canvas/Background/乘").GetComponent<Button>();
BtnMul.onClick.AddListener(() => OperationDispose("*"));
BtnDiv = GameObject.Find("Canvas/Background/除").GetComponent<Button>();
BtnDiv.onClick.AddListener(() => OperationDispose("/"));
BtnEqual = GameObject.Find("Canvas/Background/等于").GetComponent<Button>();
BtnEqual.onClick.AddListener(() => OperationDispose("="));
//数字
Btn0 = GameObject.Find("Canvas/Background/0").GetComponent<Button>();
Btn0.onClick.AddListener(() => NumDispose("0"));
Btn1 = GameObject.Find("Canvas/Background/1").GetComponent<Button>();
Btn1.onClick.AddListener(() => NumDispose("1"));
Btn2 = GameObject.Find("Canvas/Background/2").GetComponent<Button>();
Btn2.onClick.AddListener(() => NumDispose("2"));
Btn3 = GameObject.Find("Canvas/Background/3").GetComponent<Button>();
Btn3.onClick.AddListener(() => NumDispose("3"));
Btn4 = GameObject.Find("Canvas/Background/4").GetComponent<Button>();
Btn4.onClick.AddListener(() => NumDispose("4"));
Btn5 = GameObject.Find("Canvas/Background/5").GetComponent<Button>();
Btn5.onClick.AddListener(() => NumDispose("5"));
Btn6 = GameObject.Find("Canvas/Background/6").GetComponent<Button>();
Btn6.onClick.AddListener(() => NumDispose("6"));
Btn7 = GameObject.Find("Canvas/Background/7").GetComponent<Button>();
Btn7.onClick.AddListener(() => NumDispose("7"));
Btn8 = GameObject.Find("Canvas/Background/8").GetComponent<Button>();
Btn8.onClick.AddListener(() => NumDispose("8"));
Btn9 = GameObject.Find("Canvas/Background/9").GetComponent<Button>();
Btn9.onClick.AddListener(() => NumDispose("9"));
BtnPoint = GameObject.Find("Canvas/Background/点").GetComponent<Button>();
BtnPoint.onClick.AddListener(() => NumDispose("."));
BtnPm = GameObject.Find("Canvas/Background/正负").GetComponent<Button>();
BtnPm.onClick.AddListener(() => NumDispose("-"));按钮操作：
代码语言：javascript复制 //操作点击处理
private void OperationDispose(string operation)
{
switch (operation)
{
case " ":
if (RUNSTATE == 0)
TextComputeProcess.text = "0 ";
else
{
TextComputeProcess.text = TextComputeResult.text " ";
m_operation = " ";
RUNSTATE = 2;
}
break;
case "-":
if (RUNSTATE == 0)
TextComputeProcess.text = "0 - ";
else
{
TextComputeProcess.text = TextComputeResult.text " - ";
m_operation = "-";
RUNSTATE = 2;
}
break;
case "*":
if (RUNSTATE == 0)
TextComputeProcess.text = "0 * ";
else
{
TextComputeProcess.text = TextComputeResult.text " * ";
m_operation = "*";
RUNSTATE = 2;
}
break;
case "/":
if (RUNSTATE == 0)
TextComputeProcess.text = "0 / ";
else
{
TextComputeProcess.text = TextComputeResult.text " / ";
m_operation = "/";
RUNSTATE = 2;
}
break;
case "=":
if (RUNSTATE == 0)
TextComputeProcess.text = "0 = ";
else
{
if (RUNSTATE == 3)
{
double result;
switch (m_operation)
{
case " ":
result = double.Parse(calculateString) double.Parse(TextComputeResult.text);
TextComputeProcess.text = calculateString " " TextComputeResult.text " = ";
TextComputeResult.text = result.ToString();
RUNSTATE = 4;
break;
case "-":
result = double.Parse(calculateString) - double.Parse(TextComputeResult.text);
TextComputeProcess.text = calculateString " - " TextComputeResult.text " = ";
TextComputeResult.text = result.ToString();
RUNSTATE = 4;
break;
case "*":
result = double.Parse(calculateString) * double.Parse(TextComputeResult.text);
TextComputeProcess.text = calculateString " * " TextComputeResult.text " = ";
TextComputeResult.text = result.ToString();
RUNSTATE = 4;
break;
case "/":
result = double.Parse(calculateString) / double.Parse(TextComputeResult.text);
TextComputeProcess.text = calculateString " / " TextComputeResult.text " = ";
TextComputeResult.text = result.ToString();
RUNSTATE = 4;
break;
default:
break;
}
}
else
{
TextComputeProcess.text = TextComputeResult.text " = ";
}
}
break;
case "CE":
TextComputeProcess.text = "";
TextComputeResult.text = "0";
RUNSTATE = 0;
break;
case "Del":
if (RUNSTATE == 0)
return;
else
{
if (TextComputeResult.text.Length == 1)
{
TextComputeResult.text = "0";
}
else
{
TextComputeResult.text = TextComputeResult.text.Remove(TextComputeResult.text.Length - 1, 1);
}
}
break;
default:
break;
}
}数字点击处理：
代码语言：javascript复制 //数字点击处理
private void NumDispose(string num)
{
switch (num)
{
case ".":
if (RUNSTATE == 0)
TextComputeResult.text = "0";
else
TextComputeResult.text = num;
break;
case "-":
if (RUNSTATE == 0)
TextComputeResult.text = "0";
else
{
if (RUNSTATE == 1)
{
if (pmState)
{
TextComputeResult.text = TextComputeResult.text.Remove(0, 1);
pmState = false;
}
else
{
TextComputeResult.text = num TextComputeResult.text;
pmState = true;
}
}
else if (RUNSTATE == 2)
{
pmState = false;
}
else if (RUNSTATE == 3)
{
if (pmState)
{
TextComputeResult.text = TextComputeResult.text.Remove(0, 1);
pmState = false;
}
else
{
TextComputeResult.text = num TextComputeResult.text;
pmState = true;
}
}
else if (RUNSTATE == 4)
{
pmState = false;
OperationDispose("CE");
}
}
break;
default:
if (RUNSTATE == 0)
{
TextComputeResult.text = num;
RUNSTATE = 1;
}
else if (RUNSTATE == 1)
{
pmState = false;
TextComputeResult.text = num;
}
else if (RUNSTATE == 2)
{
calculateString = TextComputeResult.text;
TextComputeResult.text = "";
TextComputeResult.text = num;
RUNSTATE = 3;
}
else if (RUNSTATE == 3)
{
TextComputeResult.text = num;
}
else if (RUNSTATE == 4)
{
OperationDispose("CE");
TextComputeResult.text = num;
RUNSTATE = 1;
}
break;
}
}完整代码：
代码语言：javascript复制using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.UI;
public class CalculatorControl : MonoBehaviour
{
private Text TextComputeProcess;//计算过程
private Text TextComputeResult;//计算结果
private Button BtnReset;
private Button BtnDelete;
private Button BtnAdd;
private Button BtnSub;
private Button BtnMul;
private Button BtnDiv;
private Button BtnEqual;
private Button Btn0, Btn1, Btn2, Btn3, Btn4, Btn5, Btn6, Btn7, Btn8, Btn9;
private Button BtnPoint, BtnPm;
private string calculateString = "";//计算数
private string m_operation = "";//操作数
private bool pmState = false;//正负状态
private int RUNSTATE = 0;//0 默认 1 输入数字 2 输入操作符 3 输入操作符再输入数字 4 计算结果后
void Start()
{
//结果显示
TextComputeProcess = GameObject.Find("Canvas/Background/Image/TextComputeProcess").GetComponent<Text>();
TextComputeResult = GameObject.Find("Canvas/Background/Image/TextComputeResult").GetComponent<Text>();
TextComputeResult.text = "0";
RUNSTATE = 0;
//操作
BtnReset = GameObject.Find("Canvas/Background/重置").GetComponent<Button>();
BtnReset.onClick.AddListener(() => OperationDispose("CE"));
BtnDelete = GameObject.Find("Canvas/Background/删除").GetComponent<Button>();
BtnDelete.onClick.AddListener(() => OperationDispose("Del"));
//加减乘除
BtnAdd = GameObject.Find("Canvas/Background/加").GetComponent<Button>();
BtnAdd.onClick.AddListener(() => OperationDispose(" "));
BtnSub = GameObject.Find("Canvas/Background/减").GetComponent<Button>();
BtnSub.onClick.AddListener(() => OperationDispose("-"));
BtnMul = GameObject.Find("Canvas/Background/乘").GetComponent<Button>();
BtnMul.onClick.AddListener(() => OperationDispose("*"));
BtnDiv = GameObject.Find("Canvas/Background/除").GetComponent<Button>();
BtnDiv.onClick.AddListener(() => OperationDispose("/"));
BtnEqual = GameObject.Find("Canvas/Background/等于").GetComponent<Button>();
BtnEqual.onClick.AddListener(() => OperationDispose("="));
//数字
Btn0 = GameObject.Find("Canvas/Background/0").GetComponent<Button>();
Btn0.onClick.AddListener(() => NumDispose("0"));
Btn1 = GameObject.Find("Canvas/Background/1").GetComponent<Button>();
Btn1.onClick.AddListener(() => NumDispose("1"));
Btn2 = GameObject.Find("Canvas/Background/2").GetComponent<Button>();
Btn2.onClick.AddListener(() => NumDispose("2"));
Btn3 = GameObject.Find("Canvas/Background/3").GetComponent<Button>();
Btn3.onClick.AddListener(() => NumDispose("3"));
Btn4 = GameObject.Find("Canvas/Background/4").GetComponent<Button>();
Btn4.onClick.AddListener(() => NumDispose("4"));
Btn5 = GameObject.Find("Canvas/Background/5").GetComponent<Button>();
Btn5.onClick.AddListener(() => NumDispose("5"));
Btn6 = GameObject.Find("Canvas/Background/6").GetComponent<Button>();
Btn6.onClick.AddListener(() => NumDispose("6"));
Btn7 = GameObject.Find("Canvas/Background/7").GetComponent<Button>();
Btn7.onClick.AddListener(() => NumDispose("7"));
Btn8 = GameObject.Find("Canvas/Background/8").GetComponent<Button>();
Btn8.onClick.AddListener(() => NumDispose("8"));
Btn9 = GameObject.Find("Canvas/Background/9").GetComponent<Button>();
Btn9.onClick.AddListener(() => NumDispose("9"));
BtnPoint = GameObject.Find("Canvas/Background/点").GetComponent<Button>();
BtnPoint.onClick.AddListener(() => NumDispose("."));
BtnPm = GameObject.Find("Canvas/Background/正负").GetComponent<Button>();
BtnPm.onClick.AddListener(() => NumDispose("-"));
}
//操作点击处理
private void OperationDispose(string operation)
{
switch (operation)
{
case " ":
if (RUNSTATE == 0)
TextComputeProcess.text = "0 ";
else
{
TextComputeProcess.text = TextComputeResult.text " ";
m_operation = " ";
RUNSTATE = 2;
}
break;
case "-":
if (RUNSTATE == 0)
TextComputeProcess.text = "0 - ";
else
{
TextComputeProcess.text = TextComputeResult.text " - ";
m_operation = "-";
RUNSTATE = 2;
}
break;
case "*":
if (RUNSTATE == 0)
TextComputeProcess.text = "0 * ";
else
{
TextComputeProcess.text = TextComputeResult.text " * ";
m_operation = "*";
RUNSTATE = 2;
}
break;
case "/":
if (RUNSTATE == 0)
TextComputeProcess.text = "0 / ";
else
{
TextComputeProcess.text = TextComputeResult.text " / ";
m_operation = "/";
RUNSTATE = 2;
}
break;
case "=":
if (RUNSTATE == 0)
TextComputeProcess.text = "0 = ";
else
{
if (RUNSTATE == 3)
{
double result;
switch (m_operation)
{
case " ":
result = double.Parse(calculateString) double.Parse(TextComputeResult.text);
TextComputeProcess.text = calculateString " " TextComputeResult.text " = ";
TextComputeResult.text = result.ToString();
RUNSTATE = 4;
break;
case "-":
result = double.Parse(calculateString) - double.Parse(TextComputeResult.text);
TextComputeProcess.text = calculateString " - " TextComputeResult.text " = ";
TextComputeResult.text = result.ToString();
RUNSTATE = 4;
break;
case "*":
result = double.Parse(calculateString) * double.Parse(TextComputeResult.text);
TextComputeProcess.text = calculateString " * " TextComputeResult.text " = ";
TextComputeResult.text = result.ToString();
RUNSTATE = 4;
break;
case "/":
result = double.Parse(calculateString) / double.Parse(TextComputeResult.text);
TextComputeProcess.text = calculateString " / " TextComputeResult.text " = ";
TextComputeResult.text = result.ToString();
RUNSTATE = 4;
break;
default:
break;
}
}
else
{
TextComputeProcess.text = TextComputeResult.text " = ";
}
}
break;
case "CE":
TextComputeProcess.text = "";
TextComputeResult.text = "0";
RUNSTATE = 0;
break;
case "Del":
if (RUNSTATE == 0)
return;
else
{
if (TextComputeResult.text.Length == 1)
{
TextComputeResult.text = "0";
}
else
{
TextComputeResult.text = TextComputeResult.text.Remove(TextComputeResult.text.Length - 1, 1);
}
}
break;
default:
break;
}
}
//数字点击处理
private void NumDispose(string num)
{
switch (num)
{
case ".":
if (RUNSTATE == 0)
TextComputeResult.text = "0";
else
TextComputeResult.text = num;
break;
case "-":
if (RUNSTATE == 0)
TextComputeResult.text = "0";
else
{
if (RUNSTATE == 1)
{
if (pmState)
{
TextComputeResult.text = TextComputeResult.text.Remove(0, 1);
pmState = false;
}
else
{
TextComputeResult.text = num TextComputeResult.text;
pmState = true;
}
}
else if (RUNSTATE == 2)
{
pmState = false;
}
else if (RUNSTATE == 3)
{
if (pmState)
{
TextComputeResult.text = TextComputeResult.text.Remove(0, 1);
pmState = false;
}
else
{
TextComputeResult.text = num TextComputeResult.text;
pmState = true;
}
}
else if (RUNSTATE == 4)
{
pmState = false;
OperationDispose("CE");
}
}
break;
default:
if (RUNSTATE == 0)
{
TextComputeResult.text = num;
RUNSTATE = 1;
}
else if (RUNSTATE == 1)
{
pmState = false;
TextComputeResult.text = num;
}
else if (RUNSTATE == 2)
{
calculateString = TextComputeResult.text;
TextComputeResult.text = "";
TextComputeResult.text = num;
RUNSTATE = 3;
}
else if (RUNSTATE == 3)
{
TextComputeResult.text = num;
}
else if (RUNSTATE == 4)
{
OperationDispose("CE");
TextComputeResult.text = num;
RUNSTATE = 1;
}
break;
}
}
}效果图如下：
四、后记
完整代码278行，还是依旧那么简练，整体代码难度不大，主要是状态之间的切换： 1、输入数字的状态 2、输入操作符状态 3、输入操作符后再输入数字状态 4、计算结果后状态
理解这些状态后，代码就容易理解了。
最后，拓展一下，将其他大佬写的代码给大家看一下，大家如果觉得上面的代码太简单，可以看一下：
代码使用OnGUI搭建界面，直接拖到任意对象上就可以看到效果了：
代码语言：javascript复制using UnityEngine;
using System.Text.RegularExpressions;
using System;
public class Calculator2 : MonoBehaviour
{
public static bool IsNumeric(string value)
{
return Regex.IsMatch(value, @"^[ -]?d*[.]?d*$");
}
public string result = "";//用来显示结果
public static string str1 = "";//第一个操作数
public static bool haveDot = false;//第二个操作数
public static bool isCaclutate = false;
void OnGUI()
{
//对数字进行处理
if (GUI.Button(new Rect(100, 100, 100, 60), "CE"))
{
result = "";
str1 = "";
haveDot = false;
}
if (GUI.Button(new Rect(210, 100, 100, 60), "×") && str1.Substring(str1.Length - 1, 1) != "-" && str1.Substring(str1.Length - 1, 1) != " " && str1.Substring(str1.Length - 1, 1) != ".")
{
if (IsNumeric(str1.Substring(str1.Length - 1, 1)))
{
Debug.Log(str1.Substring(str1.Length - 1, 1));
str1 = "*";
haveDot = false;
isCaclutate = false;
}
result = str1;
}
if (GUI.Button(new Rect(320, 100, 100, 60), "÷") && str1.Substring(str1.Length - 1, 1) != "-" && str1.Substring(str1.Length - 1, 1) != " " && str1.Substring(str1.Length - 1, 1) != ".")
{
if (IsNumeric(str1.Substring(str1.Length - 1, 1)))
{
str1 = "/";
haveDot = false;
isCaclutate = false;
}
result = str1;
}
if (GUI.Button(new Rect(430, 100, 100, 60), "←"))
{
if (isCaclutate == true)
{
str1 = "";
isCaclutate = false;
}
else if (result.Length != 0)
{
str1 = str1.Substring(0, str1.Length - 1);
}
result = str1;
}
if (GUI.Button(new Rect(100, 170, 100, 60), "1"))
{
if (isCaclutate == true)
{
str1 = "";
isCaclutate = false;
haveDot = false;
}
str1 = "1";
result = str1;
}
if (GUI.Button(new Rect(210, 170, 100, 60), "2"))
{
if (isCaclutate == true)
{
str1 = "";
isCaclutate = false;
haveDot = false;
}
str1 = "2";
result = str1;
}
if (GUI.Button(new Rect(320, 170, 100, 60), "3"))
{
if (isCaclutate == true)
{
str1 = "";
isCaclutate = false;
haveDot = false;
}
str1 = "3";
result = str1;
}
if (GUI.Button(new Rect(430, 170, 100, 60), "-"))
{
if (IsNumeric(str1.Substring(str1.Length - 1, 1)) && str1.Substring(str1.Length - 1, 1) != "-" && str1.Substring(str1.Length - 1, 1) != " " && str1.Substring(str1.Length - 1, 1) != ".")
{
str1 = "-";
haveDot = false;
isCaclutate = false;
}
result = str1;
}
if (GUI.Button(new Rect(100, 240, 100, 60), "4"))
{
if (isCaclutate == true)
{
str1 = "";
isCaclutate = false;
haveDot = false;
}
str1 = "4";
result = str1;
}
if (GUI.Button(new Rect(210, 240, 100, 60), "5"))
{
if (isCaclutate == true)
{
str1 = "";
isCaclutate = false;
haveDot = false;
}
str1 = "5";
result = str1;
}
if (GUI.Button(new Rect(320, 240, 100, 60), "6"))
{
if (isCaclutate == true)
{
str1 = "";
isCaclutate = false;
haveDot = false;
}
str1 = "6";
result = str1;
}
if (GUI.Button(new Rect(430, 240, 100, 60), " ") && str1.Substring(str1.Length - 1, 1) != " " && str1.Substring(str1.Length - 1, 1) != "-" && str1.Substring(str1.Length - 1, 1) != ".")
{
if (IsNumeric(str1.Substring(str1.Length - 1, 1)))
{
str1 = " ";
haveDot = false;
isCaclutate = false;
}
result = str1;
}
if (GUI.Button(new Rect(100, 310, 100, 60), "7"))
{
if (isCaclutate == true)
{
str1 = "";
isCaclutate = false;
haveDot = false;
}
str1 = "7";
result = str1;
}
if (GUI.Button(new Rect(210, 310, 100, 60), "8"))
{
if (isCaclutate == true)
{
str1 = "";
isCaclutate = false;
haveDot = false;
}
str1 = "8";
result = str1;
}
if (GUI.Button(new Rect(320, 310, 100, 60), "9"))
{
if (isCaclutate == true)
{
str1 = "";
isCaclutate = false;
haveDot = false;
}
str1 = "9";
result = str1;
}
if (GUI.Button(new Rect(430, 310, 100, 130), "="))
{
var tmp = Evaluator.Eval(result);
Debug.Log(tmp.ToString());
result = tmp.ToString();
str1 = result;
isCaclutate = true;
if (result.Contains("."))
{
haveDot = true;
}
}
if (GUI.Button(new Rect(100, 380, 210, 60), "0"))
{
if (isCaclutate == true)
{
str1 = "";
isCaclutate = false;
haveDot = false;
}
str1 = "0";
result = str1;
}
if (GUI.Button(new Rect(320, 380, 100, 60), "."))
{
if (isCaclutate == true)
{
str1 = "0.";
isCaclutate = false;
}
if (IsNumeric(str1.Substring(str1.Length - 1, 1)) && str1.Substring(str1.Length - 1, 1) != "." && haveDot == false)
{
Debug.Log(str1.Substring(str1.Length - 1, 1));
str1 = ".";
haveDot = true;
isCaclutate = false;
}
result = str1;
}
GUI.TextArea(new Rect(100, 20, 430, 60), result);
}
/**/
/// <summary>
/// 动态求值
/// </summary>
public class Evaluator
{
/**/
/// <summary>
/// 计算结果,如果表达式出错则抛出异常
/// </summary>
/// <param name="statement">表达式,如"1 2 3 4"</param>
/// <returns>结果</returns>
public static object Eval(string statement)
{
if (statement.Trim() != string.Empty)
{
Evaluator evaluator = new Evaluator();
return evaluator.GetFormulaResult(statement);
}
else
{
return null;
}
}
private object GetFormulaResult(string s)
{
if (s == "")
{
return null;
}
string S = BuildingRPN(s);
string tmp = "";
System.Collections.Stack sk = new System.Collections.Stack();
char c = ' ';
System.Text.StringBuilder Operand = new System.Text.StringBuilder();
double x, y;
for (int i = 0; i < S.Length; i )
{
c = S[i];
//added c==',' for germany culture
if (char.IsDigit(c) || c == '.' || c == ',')
{
//数据值收集.
Operand.Append(c);
}
else if (c == ' ' && Operand.Length > 0)
{
#region 运算数转换
try
{
tmp = Operand.ToString();
if (tmp.StartsWith("-"))//负数的转换一定要小心...它不被直接支持.
{
//现在我的算法里这个分支可能永远不会被执行.
sk.Push(-((double)Convert.ToDouble(tmp.Substring(1, tmp.Length - 1))));
}
else
{
sk.Push(Convert.ToDouble(tmp));
}
}
catch
{
return null; //
}
Operand = new System.Text.StringBuilder();
#endregion
}
else if (c == ' '//运算符处理.双目运算处理.
|| c == '-'
|| c == '*'
|| c == '/'
|| c == '%'
|| c == '^')
{
#region 双目运算
if (sk.Count > 0)/*如果输入的表达式根本没有包含运算符.或是根本就是空串.这里的逻辑就有意义了.*/
{
y = (double)sk.Pop();
}
else
{
sk.Push(0);
break;
}
if (sk.Count > 0)
x = (double)sk.Pop();
else
{
sk.Push(y);
break;
}
switch (c)
{
case ' ':
sk.Push(x y);
break;
case '-':
sk.Push(x - y);
break;
case '*':
if (y == 0)
{
sk.Push(x * 1);
}
else
{
sk.Push(x * y);
}
break;
case '/':
if (y == 0)
{
sk.Push(x / 0);
}
else
{
sk.Push(x / y);
}
break;
case '%':
sk.Push(x % y);
break;
case '^'://
if (x > 0)//
{
//我原本还想,如果被计算的数是负数,又要开真分数次方时如何处理的问题.后来我想还是算了吧.
sk.Push(System.Math.Pow(x, y));
//
}
//
else//
{
//
double t = y;
//
string ts = "";
//
t = 1 / (2 * t);
//
ts = t.ToString();
//
if (ts.ToUpper().LastIndexOf('E') > 0)//
{
//
;
//
}
//
}
break;
}
#endregion
}
else if (c == '!')//单目取反. )
{
sk.Push(-((double)sk.Pop()));
}
}
if (sk.Count > 1)
{
return null;//;
}
if (sk.Count == 0)
{
return null;//;
}
return sk.Pop();
}
/**/
/// <summary>
///
/// </summary>
private string BuildingRPN(string s)
{
System.Text.StringBuilder sb = new System.Text.StringBuilder(s);
System.Collections.Stack sk = new System.Collections.Stack();
System.Text.StringBuilder re = new System.Text.StringBuilder();
char c = ' ';
//sb.Replace( " ","" );
//一开始,我只去掉了空格.后来我不想不支持函数和常量能滤掉的全OUT掉.
for (int i = 0; i < sb.Length; i )
{
c = sb[i];
//added c==',' for german culture
if (char.IsDigit(c) || c == ',')//数字当然要了.
re.Append(c);
//if( char.IsWhiteSpace( c )||
char.IsLetter(c);//如果是空白,那么不要.现在字母也不要.
//continue;
switch (c)//如果是其它字符...列出的要,没有列出的不要.
{
case ' ':
case '-':
case '*':
case '/':
case '%':
case '^':
case '!':
case '(':
case ')':
case '.':
re.Append(c);
break;
default:
continue;
}
}
sb = new System.Text.StringBuilder(re.ToString());
#region 对负号进行预转义处理.负号变单目运算符求反.
for (int i = 0; i < sb.Length - 1; i )
if (sb[i] == '-' && (i == 0 || sb[i - 1] == '('))
sb[i] = '!';
//字符转义.
#endregion
#region 将中缀表达式变为后缀表达式.
re = new System.Text.StringBuilder();
for (int i = 0;
i < sb.Length;
i )
{
if (char.IsDigit(sb[i]) || sb[i] == '.')//如果是数值.
{
re.Append(sb[i]);
//加入后缀式
}
else if (sb[i] == ' '
|| sb[i] == '-'
|| sb[i] == '*'
|| sb[i] == '/'
|| sb[i] == '%'
|| sb[i] == '^'
|| sb[i] == '!')//.
{
#region 运算符处理
while (sk.Count > 0) //栈不为空时
{
c = (char)sk.Pop();
//将栈中的操作符弹出.
if (c == '(') //如果发现左括号.停.
{
sk.Push(c);
//将弹出的左括号压回.因为还有右括号要和它匹配.
break;
//中断.
}
else
{
if (Power(c) < Power(sb[i]))//如果优先级比上次的高,则压栈.
{
sk.Push(c);
break;
}
else
{
re.Append(' ');
re.Append(c);
}
//如果不是左括号,那么将操作符加入后缀式中.
}
}
sk.Push(sb[i]);
//把新操作符入栈.
re.Append(' ');
#endregion
}
else if (sb[i] == '(')//基本优先级提升
{
sk.Push('(');
re.Append(' ');
}
else if (sb[i] == ')')//基本优先级下调
{
while (sk.Count > 0) //栈不为空时
{
c = (char)sk.Pop();
//pop Operator
if (c != '(')
{
re.Append(' ');
re.Append(c);
//加入空格主要是为了防止不相干的数据相临产生解析错误.
re.Append(' ');
}
else
break;
}
}
else
re.Append(sb[i]);
}
while (sk.Count > 0)//这是最后一个弹栈啦.
{
re.Append(' ');
re.Append(sk.Pop());
}
#endregion
re.Append(' ');
return FormatSpace(re.ToString());
//在这里进行一次表达式格式化.这里就是后缀式了.
}
/// <summary>
/// 优先级别测试函数.
/// </summary>
/// <param name="opr"></param>
/// <returns></returns>
private static int Power(char opr)
{
switch (opr)
{
case ' ':
case '-':
return 1;
case '*':
case '/':
return 2;
case '%':
case '^':
case '!':
return 3;
default:
return 0;
}
}
/// <summary>
/// 规范化逆波兰表达式.
/// </summary>
/// <param name="s"></param>
/// <returns></returns>
private static string FormatSpace(string s)
{
System.Text.StringBuilder ret = new System.Text.StringBuilder();
for (int i = 0; i < s.Length; i )
{
if (!(s.Length > i 1 && s[i] == ' ' && s[i 1] == ' '))
ret.Append(s[i]);
else
ret.Append(s[i]);
}
return ret.ToString();
//.Replace( '!','-' );
}
}
}
