代碼使用方法:
0001:
判斷一個計算結果是不是無窮大:if(isFinite(999999999*999999999) == true)
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0002:
判斷是不是數字:if(isNaN("Blue") == true),不是數字則為true,是數字則為false。
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0003:
數字的進制轉換:
var num = 10;
alert(num.toString()) + "<br>";//十進制
alert(num.toString(2)) + "<br>";//二進制
alert(num.toString(8)) + "<br>";//八進制
alert(num.toString(16)) + "<br>";//十六進制
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0004:
將字符串類型轉換為數字類型:注意,parseFloat沒有進制參數可以選擇,都當作十進制處理
var str = "10";
alert(parseInt(str,10));//字符串被當作十進制處理
alert(parseInt(str,2));//字符串被當作二進制處理
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0005:
強制類型轉換:
var str = "10";
var num = new Number(str);
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0006:
Object類的基本屬性和方法:所有類都繼承自Object,因此都有這些屬性和方法。
屬性:
●Constructor:對創建對象的函數的引用。指向構造函數。
●Prototype:對該對象的對象原型的引用。
方法:
●HasOwnProperty(property):判斷對象是不是有某個屬性。
●IsPrototypeOf(aobject):判斷該對象是不是另一個對象的原型。
●PrototypeIsEnumerable(protype):判斷屬性是否可以用for...in語句枚舉。
●ToString()
●ValueOf()
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0007:
聲明數組的幾種方法:
var array1 = new Array();
var array2 = new Array("Blue","Red","Black");
var array3 = ["Blue","Red","Black"];
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0008:
創建日期類型的方法:var myDate = new Date(Date.parse("2007/1/2"));
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0009:
URL的編碼和解碼:
var url = new String("http://www.qpsh.com?name=smartkernel");
//編碼:將非標準字符全部編碼
var enUrl = encodeURIComponent(url);//encodeURI(url);
//解碼:轉換為原始形式
var deUrl = decodeURIComponent(enUrl);//decodeURI(enUrl);
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0010:
ASP.Net中的編碼和解碼:
string url = "http://www.126.com?name=smartkernel";
string enUrl = this.Server.HtmlEncode(url);
string deUrl = this.Server.HtmlDecode(enUrl);
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0011:
靜態方法:JavaScript的靜態函數,就是聲明給構造函數的函數
}
Person.say = function(msg)
{
alert(msg);
}
Person.say("你好");
var aPerson = new Person("張三",23);
aPerson.say();
var aStringBuilder = new StringBuilder();
aStringBuilder.append("世界");
aStringBuilder.append("你好");
alert(aStringBuilder.toString());
function MyPerson(name,age)
{
this.ctorFun = Person;
this.ctorFun(name);
delete this.ctorFun;
this.Age = age;
this.sayAge = function()
{
alert(this.Age);
}
this.say = function()
{
alert(this.Name + "|" + this.Age);
}
}
var aMyPerson = new MyPerson("張三",25);
aMyPerson.sayName();
aMyPerson.sayAge();
aMyPerson.say();
function MyPerson(name,age)
{
Person.call(this,name);//或者Person.apply(this,new Array(name));
this.Age = age;
this.sayAge = function()
{
alert(this.Age);
}
this.say = function()
{
alert(this.Name + "|" + this.Age);
}
}
var aMyPerson = new MyPerson("張三",25);
aMyPerson.sayName();
aMyPerson.sayAge();
aMyPerson.say();
function MyPerson(name,age,sex)
{
Person1.call(this,name);
Person2.call(this,sex);
this.Age = age;
this.sayAge = function()
{
alert(this.Age);
}
this.say = function()
{
alert(this.Name + "|" + this.Age + "|" + this.Sex);
}
}
var aMyPerson = new MyPerson("張三",25,"男");
aMyPerson.say();
}
function MyPerson()
{
}
MyPerson.prototype = new Person();//不能有參數
function MyPerson(name,age)
{
Person.call(this,name);//或者Person.apply(this,new Array(name));
this.Age = age;
this.sayAge = function()
{
alert(this.Age);
}
this.say = function()
{
alert(this.Name + "|" + this.Age);
}
}
MyPerson.prototype = new Person();
var aMyPerson = new MyPerson("張三",25);
aMyPerson.sayName();
aMyPerson.sayAge();
aMyPerson.say();
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