//计算器
var CalcEval = function() {};
//复杂的计算方法（包含括号）
CalcEval.prototype.complexEval = function(str) {
if (str == null) {
return "";
}
if (typeof str != "string") {//转化成字符串
str = str + ""
}
var multObj = str.match(/\(([^\(\\)]*?)\)/g);//匹配括号
//不断计算最底层括号的数据
while (null != multObj)
{
var content = multObj[0] +"";
var result = this.simpleEval(content.substr(1,content.length-2));
str = str.replace(multObj[0],result);
multObj = str.match(/\(([^\(\\)]*?)\)/g);
}
return this.simpleEval(str);
};
//简单的计算方法，只有加减乘除
CalcEval.prototype.simpleEval = function(str) {
if (str == null) {
return "";
}
if (typeof str != "string") {//转化成字符串
str = str + ""
}
var valueArray = new Array();//值的数组
var markArray = new Array();//符号的数组
var tempValue = "";
var ch = str.split("");
var isOper = false;
for(var i=0; i< ch.length; i++){
if( ch[i] == "+" || ch[i] == "-" || ch[i] == "*" || ch[i] == "/") {//符号
var dv = tempValue*1;
if(isOper){
var value = valueArray.pop();
var mark = markArray.pop();
dv = this.simpleTwoEval(mark, value, dv);
}
valueArray.push(dv);
markArray.push(ch[i]);
tempValue = "";
isOper = false;
if( ch[i] == "*" || ch[i] == "/" )
isOper = true;
}else{
tempValue += ch[i] + "";
if(i == ch.length -1){//最后一位
var dv = tempValue*1;
if(isOper){
var dv1 = valueArray.pop();
var mark = markArray.pop();
var result = this.simpleTwoEval(mark, dv1, tempValue);
dv = result;
}
valueArray.push(dv);
}
}
}
valueArray = this.reverseArray(valueArray);
markArray = this.reverseArray(markArray);
while(valueArray.length > 1){
var v1 = valueArray.pop();
var v2 = valueArray.pop();
var mark = markArray.pop();
valueArray.push(this.simpleTwoEval(mark, v1, v2));
}
return valueArray[0];
};
//两个数的加减乘除
CalcEval.prototype.simpleTwoEval = function(mark,value1,value2){
if(mark == "+"){
return value1 + value2;
}else if(mark == "-"){
return value1 - value2;
}else if(mark == "*"){
return value1 * value2;
}else if(mark == "/"){
return value1 / value2;
}
return 0;
};
//反转数组
CalcEval.prototype.reverseArray = function(oldArray){
var newArray = new Array();
var size = oldArray.length;
for(var i=0; i< size; i++){
newArray.push(oldArray.pop());
}
return newArray;
};
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