一、JavaScript惰性函数
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function
createXHR(){
var
xhr =
null
;
try
{
//FireFox,Opera 8.0+,Safari,IE7+
xhr =
new
XMLHttpRequest();
}
catch
(e){
//Internet Explorer
try
{
xhr =
new
ActiveXObject(
"Msxml2.XMLHTTP"
);
}
catch
(e){
try
{
xhr =
new
ActiveXObject(
"MicroSoft.XMLHTTP"
);
}
catch
(e){
xhr =
null
;
}
}
}
return
xhr;
}
//function handleErr(err){
// var errXHR = err;
//
//}
/*惰性函数*/
//第二次生效
function
createXHR(){
var
xhr =
null
;
if
(
typeof
XMLHttpRequest !=
'undefined'
){
xhr =
new
XMLHttpRequest();
createXHR =
function
(){
return
new
XMLHttpRequest();
}
}
else
{
try
{
xhr =
new
ActiveXObject(
"Msxml2.XMLHTTP"
);
createXHR =
function
(){
return
new
ActiveXObject(
"Msxml2.XMLHTTP"
);
}
}
catch
(e){
try
{
xhr =
new
ActiveXObject(
"MicroSoft.XMLHTTP"
);
createXHR =
function
(){
return
new
ActiveXObject(
"MicroSoft.XMLHTTP"
);
}
}
catch
(e){
createXHR() =
function
(){
return
null
;
}
}
}
}
return
xhr;
}
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二、函数科里化
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function
curry(fn){
var
args = Array.prototype.slice.call(arguments,1);
return
function
(){
var
innerArgs = Array.prototype.slice.call(arguments);
var
finalArgs = args.concat(innerArgs);
console.log(finalArgs);
return
fn.apply(
this
,finalArgs);
}
}
function
add(num1,num2,num3){
return
num1+num2+num3;
}
var
t = curry(add,50)(1,2);
alert(t);
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三、级联函数
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function
classA(){
this
.face =
""
;
this
.mouse =
""
;
this
.leg =
""
;
}
classA.prototype = {
setFace:
function
(){
this
.face =
"红扑扑"
;
}
setMouse:
function
(){
this
.mouse =
"大嘴"
;
}
setLeg:
function
(){
this
.leg =
"长腿欧巴"
;
}
};
var
person =
new
classA();
person.setFace();
person.setMouse();
person.setLeg();
console.log(person);
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本文转自yeleven 51CTO博客，原文链接:http://blog.51cto.com/11317783/1794399
