var print;
if(typeof document != "undefined" ){
print = function(){
document.write(arguments[0]);
}
}else if(typeof WScript != "undefined" ){
print = function(){
WScript.Echo(arguments[0],arguments[1],arguments[2]);
}
}
function empty(){
}
function benchmark(f){
var i = 0;
var start = (new Date()).getTime();
while(i < pressure){
f(i++);
}
var end = (new Date()).getTime();
WScript.Echo(end-start);
}
/*
i=0
start = (new Date()).getTime();
while(i < 60000){
c = [i,i,i,i,i,i,i,i,i,i];
i++;
}
end = (new Date()).getTime();
WScript.Echo(end-start);
i=0
start = (new Date()).getTime();
while(i < 60000){
c = new Array(i,i,i,i,i,i,i,i,i,i);
i++;
}
var end = (new Date()).getTime();
WScript.Echo(end-start);
*/
function internCast(i){
return "" + i;
}
function StringCast(i){
return String(i)
}
function newStringCast(i){
return new String(i)
}
function toStringCast(i){
return i.toString();
}
function ParseInt(){
return parseInt(j);
}
function MathFloor(){
return Math.floor(j);
}
function Floor(){
return floor(j);
}
var pressure = 50000;
var a = "";
var floor = Math.floor;
j = 123.123;
print("-------------\nString Conversion Test");
print("The empty:", benchmark(empty));
print("intern:", benchmark(internCast));
print("String:");
benchmark(StringCast);
print("new String:");
benchmark(newStringCast);
print("toString:");
benchmark(toStringCast);
print("-------------\nFloat to Int Conversion Test");
print("parseInt");
benchmark(ParseInt);
print("Math.floor");
benchmark(MathFloor);
print("floor")
benchmark(Floor);
function newObject(){
return new Object();
}
function internObject(){
return {};
}
print("------------\nliteral Test");
print("runtime new object", benchmark(newObject));
print("literal object", benchmark(internObject));
附录2
代码1：
复制代码 代码如下:
for(var i=0;i<100;i++){
arr[i]=0;
}
代码2：
复制代码 代码如下:
var i = 0;
while(i < 100){
arr[i++]=0;
}
代码3：
复制代码 代码如下: