29 lines
468 B
JavaScript
29 lines
468 B
JavaScript
function Calculator() {
|
|
|
|
var methods = {
|
|
"-": function(a, b) {
|
|
return a - b;
|
|
},
|
|
"+": function(a, b) {
|
|
return a + b;
|
|
}
|
|
};
|
|
|
|
this.calculate = function(str) {
|
|
|
|
var split = str.split(' '),
|
|
a = +split[0],
|
|
op = split[1],
|
|
b = +split[2]
|
|
|
|
if (!methods[op] || isNaN(a) || isNaN(b)) {
|
|
return NaN;
|
|
}
|
|
|
|
return methods[op](a, b);
|
|
}
|
|
|
|
this.addMethod = function(name, func) {
|
|
methods[name] = func;
|
|
};
|
|
}
|