四则运算计算器的微信小程序_2 运算

js文件：

function isOperator(value) {

  var operatorString = '+-*/()×÷';

  return operatorString.indexOf(value) > -1;

}

function getPrioraty(value) {

  if(value == '-' || value == '+') {

    return 1;

  } else if(value == '*' || value == '/' || value == '×' || value == '÷' ) {

    return 2;

  } else{

    return 0;

  }

}

function prioraty(v1, v2) {

  return getPrioraty(v1) <= getPrioraty(v2);

}

function outputRpn(exp) {

  var inputStack = [];

  var outputStack = [];

  var outputQueue = [];

  var firstIsOperator = false;

  exp.replace(/\s/g,'');

  if(isOperator(exp[0])){

    exp = exp.substring(1);

    firstIsOperator = true;

  }

  for(var i = 0, max = exp.length; i < max; i++) {

    if(!isOperator(exp[i]) && !isOperator(exp[i-1]) && (i != 0)) {

      inputStack[inputStack.length-1] = inputStack[inputStack.length-1] + exp[i] + '';

    } else {

      inputStack.push(exp[i]);

    }

  }

  if(firstIsOperator) {

    inputStack[0] = -inputStack[0]

  }

  while(inputStack.length > 0) {

    var cur = inputStack.shift();

    if(isOperator(cur)) {

      if (cur == '(') {

        outputStack.push(cur);

      } else if (cur == ')') {

        var po = outputStack.pop();

        while(po != '(' && outputStack.length > 0) {

          outputQueue.push(po);

          po = outputStack.pop();

        }

      } else {

        while(prioraty(cur,outputStack[outputStack.length - 1]) && outputStack.length > 0) {

          outputQueue.push(outputStack.pop());

        }

        outputStack.push(cur)

      }

    } else {

      outputQueue.push(Number(cur));

    }

  }

  if(outputStack.length > 0){

    while (outputStack.length > 0) {

      outputQueue.push(outputStack.pop());

    }

  }

  return outputQueue;

}

function calRpnExp(rpnArr) {

  var stack = [];

  for(var i = 0, max = rpnArr.length; i < max; i++) {

    if(!isOperator(rpnArr[i])) {

      stack.push(rpnArr[i]);

    } else {

      var num1 = stack.pop();

      var num2 = stack.pop();

      if(rpnArr[i] == '-') {

        var num = num2 - num1;

      } else if(rpnArr[i] == '+') {

        var num = num2 + num1;

      } else if(rpnArr[i] == '*' || rpnArr[i] == '×') {

        var num = num2 * num1;

      } else if(rpnArr[i] == '/' || rpnArr[i] == '÷') {

        var num = num2/num1;

      }

      stack.push(num);

    }

  }

  return stack[0];

}

function calCommonExp(exp) {

  var rpnArr = outputRpn(exp);

  return calRpnExp(rpnArr)

}

module.exports = {

  isOperator: isOperator,

  getPrioraty: getPrioraty,

  outputRpn: outputRpn,

  calRpnExp: calRpnExp,

  calCommonExp: calCommonExp

}

 

 

function formatTime(date) {

var year = date.getFullYear()

var month = date.getMonth() + 1

var day = date.getDate()

var hour = date.getHours()

var minute = date.getMinutes()

var second = date.getSeconds()

return [year, month, day].map(formatNumber).join('/') + ' ' + [hour, minute, second].map(formatNumber).join(':')

}

function formatNumber(n) {

n = n.toString()

return n[1] ? n : '0' + n

}

module.exports = {

formatTime: formatTime

}

 

//index.js

//获取应用实例

var rpn = require("../../utils/rpn.js");

var app = getApp()

Page({

data: {

id1:"back",

id2:"clear",

id3:"negative",

id4:"+",

id5:"9",

id6:"8",

id7:"7",

id8:"-",

id9:"6",

id10:"5",

id11:"4",

id12:"×",

id13:"3",

id14:"2",

id15:"1",

id16:"÷",

id17:"0",

id18:".",

id19:"history",

id20:"=",

screenData:"0",

lastIsOperator: false,

logs: []

},

//事件处理函数

 

onLoad: function () {

 

},

onReady: function () {

},

onShow: function () {

},

onHide: function () {

},

onUpload: function () {

},

history: function () {

wx.navigateTo({

url:'../list/list'

})

},

clickButton: function (event) {

console.log(event);

var data = this.data.screenData.toString();

var id = event.target.id;

if(id == this.data.id1) {

if(data == 0){

return;

}

console.log(data);

console.log("data.substring(0,data.length-1)"+data.substring(0,data.length-1));

var data = data.substring(0,data.length-1);

console.log(data);

} else if(id == this.data.id2) {

data = 0;

} else if (id == this.data.id3) {

var firstWord = data.substring(0,1);

if(firstWord != '-'){

data = '-' + data;

} else {

data = data.substring(1);

}

} else if (id == this.data.id20){

if(data == 0) {

return;

}

var lastWord = data.substring(data.length-1, data.length);

if(isNaN(lastWord)) {

return;

}

console.log("parseFloat(data)"+parseFloat(data));

console.log("data"+data)

if(parseFloat(data) == data){

return;

}

var log = data;

var data = rpn.calCommonExp(data);

log = log + '=' +data;

this.data.logs.push(log);

wx.setStorageSync('callogs',this.data.logs)

console.log(wx.getStorageSync('callogs'));

} else {

if(id == this.data.id4 || id == this.data.id8 || id == this.data.id12 || id == this.data.id16) {

if(this.data.lastIsOperator || data == 0) {

return;

}

}

if(data == 0) {

data = id;

} else {

data = data + id

}

if(id == this.data.id4 || id == this.data.id8 || id == this.data.id12 || id == this.data.id16) {

this.setData({lastIsOperator:true});

} else {

this.setData({lastIsOperator:false})

}

}

this.setData({

screenData:data

})

}

})

 

 

 

//获取应用实例

var app = getApp()

Page({

data: {

logs:[]

},

onLoad: function () {

var logs =wx.getStorageSync('callogs');

this.data.logs=logs;

}

})

（原项目作者：忽如寄 （简书）

原文链接：https://www.jianshu.com/p/47c1a65009a7）