JavaScript方法和技巧大全_基础知识

有些时候你精通一门语言，但是会发现你其实整天在和其它语言打交道，也许你以为这些微不足道，不至于影响你的开发进度，但恰恰是这些你不重视的东西会浪费你很多时间，我一直以为我早在几年前就已经精通JavaScript了，直到目前，我才越来越觉得JavaScript远比我想象的复杂和强大，我开始崇拜它，就像崇拜所有OOP语言一样～
趁着节日的空隙，把有关JavaScript的方法和技巧整理下，让每个在为JavaScript而烦恼的人明白，JavaScript就这么回事！并希望JavaScript还可以成为你的朋友，让你豁然开朗，在项目中更好的应用～

适合阅读范围：对JavaScript一无所知～离精通只差一步之遥的人
基础知识：HTML

JavaScript就这么回事1：基础知识

1 创建脚本块

1:
2: JavaScript code goes here
3:

2 隐藏脚本代码

1:
2: 3: document.write(“Hello”);
4: // -->
5:

在不支持JavaScript的浏览器中将不执行相关代码

3 浏览器不支持的时候显示

1:

4 链接外部脚本文件

1: 输出到浏览器

1: document.write(“Hello”);

7 定义变量

1: var myVariable = “some value”;

8 字符串相加

1: var myString = “String1” + “String2”;

9 字符串搜索

1:
2: 3: var myVariable = “Hello there”;
4: var therePlace = myVariable.search(“there”);
5: document.write(therePlace);
6: // -->
7:

10 字符串替换

1: thisVar.replace(“Monday”,”Friday”);

11 格式化字串

1:
2: 3: var myVariable = “Hello there”;
4: document.write(myVariable.big() + “
”);
5: document.write(myVariable.blink() + “
”);
6: document.write(myVariable.bold() + “
”);
7: document.write(myVariable.fixed() + “
”);
8: document.write(myVariable.fontcolor(“red”) + “
”);
9: document.write(myVariable.fontsize(“18pt”) + “
”);
10: document.write(myVariable.italics() + “
”);
11: document.write(myVariable.small() + “
”);
12: document.write(myVariable.strike() + “
”);
13: document.write(myVariable.sub() + “
”);
14: document.write(myVariable.sup() + “
”);
15: document.write(myVariable.toLowerCase() + “
”);
16: document.write(myVariable.toUpperCase() + “
”);
17:
18: var firstString = “My String”;
19: var finalString = firstString.bold().toLowerCase().fontcolor(“red”);
20: // -->
21:

12 创建数组

1:
2: 3: var myArray = new Array(5);
4: myArray[0] = “First Entry”;
5: myArray[1] = “Second Entry”;
6: myArray[2] = “Third Entry”;
7: myArray[3] = “Fourth Entry”;
8: myArray[4] = “Fifth Entry”;
9: var anotherArray = new Array(“First Entry”,”Second Entry”,”Third Entry”,”Fourth Entry”,”Fifth Entry”);
10: // -->
11:

13 数组排序

1:
2: 3: var myArray = new Array(5);
4: myArray[0] = “z”;
5: myArray[1] = “c”;
6: myArray[2] = “d”;
7: myArray[3] = “a”;
8: myArray[4] = “q”;
9: document.write(myArray.sort());
10: // -->
11:

14 分割字符串

1:
2: 3: var myVariable = “a,b,c,d”;
4: var stringArray = myVariable.split(“,”);
5: document.write(stringArray[0]);
6: document.write(stringArray[1]);
7: document.write(stringArray[2]);
8: document.write(stringArray[3]);
9: // -->
10:

15 弹出警告信息

1:
2: 3: window.alert(“Hello”);
4: // -->
5:

16 弹出确认框

1:
2: 3: var result = window.confirm(“Click OK to continue”);
4: // -->
5:

17 定义函数

1:
2: 3: function multiple(number1,number2) {
4: var result = number1 * number2;
5: return result;
6: }
7: // -->
8:

18 调用JS函数

1: Link text
2: Link text

19 在页面加载完成后执行函数

1:
2: Body of the page
3:

20 条件判断

1:
2: 3: var userChoice = window.confirm(“Choose OK or Cancel”);
4: var result = (userChoice == true) ? “OK” : “Cancel”;
5: document.write(result);
6: // -->
7:

21 指定次数循环

1:
2: 3: var myArray = new Array(3);
4: myArray[0] = “Item 0”;
5: myArray[1] = “Item 1”;
6: myArray[2] = “Item 2”;
7: for (i = 0; i < myArray.length; i++) {
8: document.write(myArray[i] + “
”);
9: }
10: // -->
11:

22 设定将来执行

1:
2: 3: function hello() {
4: window.alert(“Hello”);
5: }
6: window.setTimeout(“hello()”,5000);
7: // -->
8:

23 定时执行函数

1:
2: 3: function hello() {
4: window.alert(“Hello”);
5: window.setTimeout(“hello()”,5000);
6: }
7: window.setTimeout(“hello()”,5000);
8: // -->
9:

24 取消定时执行

1: 输出

26 访问document对象

1: 输出HTML

1: 输出换行

1: document.writeln(“a”);
2: document.writeln(“b”);

29 输出日期

1:
2: var thisDate = new Date();
3: document.write(thisDate.toString());
4:

30 指定日期的时区

1: 输出格式

1:
2: var thisDate = new Date();
3: var thisTimeString = thisDate.getHours() + “:” + thisDate.getMinutes();
4: var thisDateString = thisDate.getFullYear() + “/” + thisDate.getMonth() + “/” + thisDate.getDate();
5: document.write(thisTimeString + “ on “ + thisDateString);
6:

32 读取URL参数

1:
2: var urlParts = document.URL.split(“?”);
3: var parameterParts = urlParts[1].split(“&”);
4: for (i = 0; i < parameterParts.length; i++) {
5: var pairParts = parameterParts[i].split(“=”);
6: var pairName = pairParts[0];
7: var pairValue = pairParts[1];
8: document.write(pairName + “ ：“ +pairValue );
9: }
10:

你还以为HTML是无状态的么？

33 打开一个新的document对象

1:
2: function newDocument() {
3: document.open();
4: document.write(“

This is a New Document.

34 页面跳转

1:
2: window.location = “http://www.liu21st.com/”;
3:

35 添加网页加载进度窗口

1:
2:
3:
4: var placeHolder = window.open('holder.html','placeholder','width=200,height=200');
5:
6:
7:
8:
9:

This is the main page

JavaScript就这么回事3：图像

36 读取图像属性

1:
2: Width
3:

37 动态加载图像

1:
2: myImage = new Image;
3: myImage.src = “Tellers1.jpg”;
4:

38 简单的图像替换

1:
2: rollImage = new Image;
3: rollImage.src = “rollImage1.jpg”;
4: defaultImage = new Image;
5: defaultImage.src = “image1.jpg”;
6:
7: 8: onMouseOut=”document.myImage.src = defaultImage.src;”>
9:

39 随机显示图像

1:
2: var imageList = new Array;
3: imageList[0] = “image1.jpg”;
4: imageList[1] = “image2.jpg”;
5: imageList[2] = “image3.jpg”;
6: imageList[3] = “image4.jpg”;
7: var imageChoice = Math.floor(Math.random() * imageList.length);
8: document.write(‘
17:

41 创建幻灯片

1:
2: var imageList = new Array;
3: imageList[0] = new Image;
4: imageList[0].src = “image1.jpg”;
5: imageList[1] = new Image;
6: imageList[1].src = “image2.jpg”;
7: imageList[2] = new Image;
8: imageList[2].src = “image3.jpg”;
9: imageList[3] = new Image;
10: imageList[3].src = “image4.jpg”;
11: function slideShow(imageNumber) {
12: document.slideShow.src = imageList[imageNumber].src;
13: imageNumber += 1;
14: if (imageNumber < imageList.length) {
15: window.setTimeout(“slideShow(“ + imageNumber + “)”,3000);
16: }
17: }
18:
19:
20:
21:

42 随机广告图片

1:
2: var imageList = new Array;
3: imageList[0] = “image1.jpg”;
4: imageList[1] = “image2.jpg”;
5: imageList[2] = “image3.jpg”;
6: imageList[3] = “image4.jpg”;
7: var urlList = new Array;
8: urlList[0] = “http://some.host/”;
9: urlList[1] = “http://another.host/”;
10: urlList[2] = “http://somewhere.else/”;
11: urlList[3] = “http://right.here/”;
12: var imageChoice = Math.floor(Math.random() * imageList.length);
13: document.write(‘
3:
4:
5: 在frame1中加载frame2中的页面
6: parent.frame2.document.location = “135b.html”;

68 在框架页面之间共享脚本
如果在frame1中html文件中有个脚本

1: function doAlert() {
2: window.alert(“Frame 1 is loaded”);
3: }

那么在frame2中可以如此调用该方法

1:
2: This is frame 2.
3:

69 数据公用
可以在框架页面定义数据项，使得该数据可以被多个框架中的页面公用

1:
2: var persistentVariable = “This is a persistent value”;
3:
4:
5:
6:
7:

这样在frame1和frame2中都可以使用变量persistentVariable
70 框架代码库
根据以上的一些思路，我们可以使用一个隐藏的框架页面来作为整个框架集的代码库

1:
2:
3:
4:
5: