用js实现的辣鸡计算器。。已解决切换运算符

2018-11-08

2247 次瀏覽

427字数

## 用js实现的辣鸡计算器。。利用正则表达式，已解决切换运算符 ##

主要利用eval()这个函数实现，<del>但连续点击换算符的bug没想到..</del>
然后就没去实现open＆turnoff
![simple-count][1]
测试地址：[simple-count][2]
    window.onload = function(){
        var computer= "0";
        var num = document.getElementById("num");
        var cR = document.getElementById("countResult");
        var Abutton = new Array();
        Abutton = document.getElementsByTagName('button');
        for(var a=0;a<Abutton.length;a++){
            let j=a;
            //0为开机 1为关机 2为取余 3为清除 7为加 11为减 15为乘 18为等于 19为除
            /*思路： 每当点击运算符按钮时就要执行 先把id为num的标签的内容计算后，
            再通过innertext方法赋值并覆盖一次num标签的内容
            */
            if(a=="0"){
                
            }else if(a=="1"){
                
            }else if(a=="2"){
                Abutton[a].onclick = function(){
                    doCount();
                    num.innerHTML=num.innerText+Abutton[j].value;
                };
            }else if(a=="3"){
                Abutton[a].onclick =function(){
                    firstDo();
                    num.innerHTML="0";
                    secondDo();
                };
            }else if(a=="7"){
                Abutton[a].onclick = function(){
                    doCount();
                    num.innerHTML=num.innerText+Abutton[j].value;
                };
            }else if(a=="11"){
                Abutton[a].onclick = function(){
                    doCount();
                    num.innerHTML=num.innerText+Abutton[j].value;
                };
            }else if(a=="15"){
                Abutton[a].onclick = function(){
                    doCount();
                    num.innerHTML=num.innerText+Abutton[j].value;
                };
            }else if(a=="18"){
                Abutton[a].onclick = function (){
                    doCount();
                    var getResult = num.innerText;
                    firstDo();
                    cR.innerHTML = getResult;
                };
            }else if(a=="19"){
                Abutton[a].onclick = function(){
                    doCount();
                    num.innerHTML=num.innerText+Abutton[j].value;
                };
            }else{
                Abutton[a].onclick =function(){
                    if(num.innerText=="0"){
                        firstDo();
                    }
                    num.innerHTML=num.innerText+Abutton[j].value;
                    secondDo();
                };
            }
        }
    };
    function firstDo(){
        num.innerHTML="";
    }
    function secondDo(){
        var cR = document.getElementById("countResult");
        cR.innerHTML="";
    }
    function doCount(){
        if(num.innerText==""){
            var cR = document.getElementById("countResult");
            var cRsource = cR.innerText;
            num.innerHTML= cRsource;
        }
        var sourceProblem = num.innerText;
        var newValue=eval(sourceProblem);
        num.innerHTML=newValue;
        secondDo();
    }

正则表达式写法，编写一个函数并置于doCount函数里的第一条执行语句

function ifExist(){
       var sourceProblem = num.innerText;
       console.log("sourceproblem的值为："+sourceProblem);
       var patt = /[\+\-\u002A\u002f\%]$/;
       if(patt.test(sourceProblem)){
           sourceProblem = sourceProblem.replace(patt,"");
           num.innerHTML=sourceProblem;
       }
    }

[GitHub地址][3]

[1]: https://raw.githubusercontent.com/susdevlop/simple-count/master/images/simple-count.png
  [2]: https://sushome.us/Testsite/simple-count/count.html
  [3]: https://github.com/susdevlop/simple-count

最后修改：2019-02-07