小程序计算器

                        {{item}}              {{currentEnd}}  

/**index.wxss**/.body{  width: 100%;  height: 100vh;  background-color: black;  /* 使用flex布局 */  display: flex;  flex-direction: column-reverse;}/* 顶部显示结果 */.end{  width: 100%;  height: 25%;/* 动态设置 */  /* background-color: red;  */  position: relative;}.end text{  position: absolute;  bottom: 0;  right: 5px;  font-size: 60px;  color: white;}/* 底部的按钮 */.bottom{  width: 100%;  height: 450px;/* 5×90px */  background-color: green;}/* 按钮的整体样式 设置高度为90px */.bottom .item{  display: inline-block;  width: 25%;  height: 90px;  background-color: #666666;  /* 字体设置 */  color: white;  text-align: center;  line-height: 90px;  font-size: 20px;  /* 边框设置 */  border: 1px solid #eeeeee;  box-sizing: border-box;}.bottom .gray{  background-color: gray;  color: black;}.bottom .orange{  background-color: orange;  color: white;}/* 单独占两个位置 */.bottom .twoItem{  width: 50%;}

//index.js//微信小程序不能使用eval函数了，所以引用一个代替eval函数的var Binding = require('../../tools/Binding.js');Page({  data: {    //底部功能按钮数组    array: ['AC', '+/-', '%',"÷",            '7','8','9','×',            '4','5','6','-',            '1','2','3','+',            '0','.','='],    currentEnd: '0',//当前的结果    operator: '',//记录运算符式  },  bindtap: function(res){    //获取点击的// console.log(res.currentTarget.dataset.index);    var index = res.currentTarget.dataset.index;    //取出当前的值    var currentEnd = this.data.currentEnd;    //查看当前的运算符    var operator = this.data.operator;    //下面处理点击事件    if (index == 0){      //AC按钮点击 清空      currentEnd = '0';      operator = '';    }else if (index == 1){      //正负取反      //如果最后一位是运算符就不做处理      var endW = operator.substr(-1, 1);      if (endW == '%' || endW == '/' || endW == '*' || endW == '+' || endW == '-') {        console.log("最后是运算符，不做处理");      }else{        //正负取反处理        var str = operator.substr(0, operator.length - (currentEnd + '').length);        currentEnd = currentEnd * 1;        currentEnd = -currentEnd;        operator = str + (currentEnd + '');      }    } else if (index == 17) {      //小数点点击      //如果最后一位是运算符就不做处理      var endW = operator.substr(-1, 1);      if (endW == '%' || endW == '/' || endW == '*' || endW == '+' || endW == '-') {        console.log("最后是运算符，不做处理");      } else {        //小数点点击处理        if ((currentEnd + '').indexOf('.') == -1) {          currentEnd = currentEnd + '.';          operator += '.';        } else {          console.log('已经是小数了，不做处理');        }      }    } else if (index == 18) {      //等号点击      //判断最后一位      //最后一位是运算符就去掉      //最后一位是小数点也去掉      var endW = operator.substr(-1, 1);      if (endW == '%' || endW == '/' || endW == '*' || endW == '+' || endW == '-' || endW == '.') {        operator = operator.substr(0, operator.length - 1);      }      //等号点击运算结果      currentEnd = wx.binding.eval(operator);      //再次点击从新开始      operator = '';    }    /* 下面是运算符类 */    else if (index == 2) {      //运算符'%';      operator = this.fuhaoFun(operator,'%');    } else if (index == 3) {      //运算符'/';      operator = this.fuhaoFun(operator, '/');    } else if (index == 7) {      //运算符'*';      operator = this.fuhaoFun(operator, '*');    } else if (index == 11) {      //运算符'-';      operator = this.fuhaoFun(operator, '-');    } else if (index == 15) {      //运算符'+';      operator = this.fuhaoFun(operator, '+');    }     /* 剩下的都是数字 */    else if (index == 16){      //数字0      currentEnd = this.yunsuanFun(operator, currentEnd, 0);      operator += '0';    }else if (index == 4) {      //数字7      currentEnd = this.yunsuanFun(operator, currentEnd, 7);      operator += '7';    }else if (index == 5) {      //数字8      currentEnd = this.yunsuanFun(operator, currentEnd, 8);      operator += '8';    }else if (index == 6) {      //数字9      currentEnd = this.yunsuanFun(operator, currentEnd, 9);      operator += '9';    }else if (index == 8) {      //数字4      currentEnd = this.yunsuanFun(operator, currentEnd, 4);      operator += '4';    }else if (index == 9) {      //数字5      currentEnd = this.yunsuanFun(operator, currentEnd, 5);      operator += '5';    }else if (index == 10) {      //数字6      currentEnd = this.yunsuanFun(operator, currentEnd, 6);      operator += '6';    }else if (index == 12) {      //数字1      currentEnd = this.yunsuanFun(operator, currentEnd, 1);      operator += '1';    }else if (index == 13) {      //数字2      currentEnd = this.yunsuanFun(operator, currentEnd, 2);      operator += '2';    }else if (index == 14) {      //数字3      currentEnd = this.yunsuanFun(operator,currentEnd,3);      operator += '3';    }    console.log(operator+'====='+currentEnd);    //所有情况处理完赋值    this.setData({      currentEnd: currentEnd,      operator: operator,    })  },  //输入的是数字的时候进行运算  yunsuanFun: function (operator,currentEnd,num){    //判断是否是重新开始的    if (operator.length == 0){      currentEnd = num;      return currentEnd;    }    //不是重新开始的运算    var endW = operator.substr(-1,1);    if (endW == '%' || endW == '/' || endW == '*' || endW == '+' || endW == '-'){      currentEnd = num;    }else{      if (currentEnd == 0) {        //初始时点击数字        currentEnd = num;      }else{        currentEnd = currentEnd + '' + num;      }    }    return currentEnd;  },  //输入的是运算符的时候进行运算  fuhaoFun: function(operator,fuhao){    //点击了等号后点击了运算符    if(operator.length == 0){      operator = 0+fuhao;      return operator;    }    //判断是不是运算符    var endW = operator.substr(-1, 1);    if (endW == '%' || endW == '/' || endW == '*' || endW == '+' || endW == '-') {      //把最后一个运算符进行替换掉      operator = operator.substr(0,operator.length-1);      operator += fuhao;    }else if(endW == '.'){      //最后一位为小数点的情况      operator = operator + '0' + fuhao;    }else{      //直接添加运算符      operator += fuhao;    }    return operator;  }})