JavaScript新的认识

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

JavaScript就这么回事1：基础知识

1 创建脚本块

JavaScript code goes here

</script>

2 隐藏脚本代码

<!--

document.write("Hello");

// -->

</script>

3 在不支持JavaScript的浏览器中将不执行相关代码,浏览器不支持的时候显示

Hello to the non-JavaScript browser.

</noscript>

4 链接外部脚本文件

5 注释脚本

// This is a comment

document.write("Hello"); // This is a comment

All of this

is a comment

6 输出到浏览器

document.write("<strong>Hello</strong>");

7 定义变量

var myVariable = "some value";

8 字符串相加

var myString = "String1" + "String2";

9 字符串搜索

<!--

var myVariable = "Hello there";

var therePlace = myVariable.search("there");

document.write(therePlace);

// -->

</script>

10 字符串替换

thisVar.replace("Monday","Friday");

11 格式化字串

<!--

var myVariable = "Hello there";

document.write(myVariable.big() + "<br>");

document.write(myVariable.blink() + "<br>");

document.write(myVariable.bold() + "<br>");

document.write(myVariable.fixed() + "<br>");

document.write(myVariable.fontcolor("red") + "<br>");

document.write(myVariable.fontsize("18pt") + "<br>");

document.write(myVariable.italics() + "<br>");

document.write(myVariable.small() + "<br>");

document.write(myVariable.strike() + "<br>");

document.write(myVariable.sub() + "<br>");

document.write(myVariable.sup() + "<br>");

document.write(myVariable.toLowerCase() + "<br>");

document.write(myVariable.toUpperCase() + "<br>");

var firstString = "My String";

var finalString = firstString.bold().toLowerCase().fontcolor("red");

// -->

</script>

12 创建数组

<!--

var myArray = new Array(4);

myArray[0] = "First Entry";

myArray[1] = "Second Entry";

myArray[2] = "Third Entry";

myArray[3] = "Fourth Entry";

var anotherArray = new Array("First Entry","Second Entry","Third Entry","Fourth Entry");

// -->

</script>

13 数组排序

<!--

var myArray = new Array(4);

myArray[0] = "z";

myArray[1] = "c";

myArray[2] = "d";

myArray[3] = "a";

document.write(myArray.sort());

// -->

</script>

14 分割字符串

<!--

var myVariable = "a,b,c,d";

var stringArray = myVariable.split(",");

document.write(stringArray[0]);

document.write(stringArray[1]);

document.write(stringArray[2]);

document.write(stringArray[3]);

// -->

</script>

15 弹出警告信息

<!--

window.alert("Hello");

// -->

</script>

16 弹出确认框

<!--

var result = window.confirm("Click OK to continue");

// -->

</script>

17 定义函数

<!--

function multiple(number1,number2) {

var result = number1 * number2;

return result;

}

// -->

</script>

18 调用JS函数

19 在页面加载完成后执行函数

Body of the page

</body>

20 条件判断

<!--

var userChoice = window.confirm("Choose OK or Cancel");

var result = (userChoice == true) ? "OK" : "Cancel";

document.write(result);

// -->

</script>

21 指定次数循环

<!--

var myArray = new Array(3);

myArray[0] = "Item 0";

myArray[1] = "Item 1";

myArray[2] = "Item 2";

for (i = 0; i < myArray.length; i++) {

document.write(myArray + "<br>");

}

// -->

</script>

22 设定将来执行,延时5秒

<!--

function hello() {

window.alert("Hello");

}

window.setTimeout("hello()",5000);

// -->

</script>

23 定时执行函数

<!--

function hello() {

window.alert("Hello");

window.setTimeout("hello()",5000);

}

hello();

// -->

</script>

24 取消定时执行

<!--

function hello() {

window.alert("Hello");

}

var myTimeout = window.setTimeout("hello()",5000);

window.clearTimeout(myTimeout);

// -->

</script>

25 在页面卸载时候执行函数

Body of the page

</body>

avaScript就这么回事2：浏览器输出

26 访问document对象

var myURL = document.URL;

window.alert(myURL);

</script>

27 动态输出HTML

document.write("<p>Here's some information about this document:</p>");

document.write("<ul>");

document.write("<li>Referring Document: " + document.referrer + "</li>");

document.write("<li>Domain: " + document.domain + "</li>");

document.write("<li>URL: " + document.URL + "</li>");

document.write("</ul>");

</script>

28 输出换行

document.writeln("<strong>a</strong>");

document.writeln("b");

29 输出日期

var thisDate = new Date();

document.write(thisDate.toString());

</script>

30 指定日期的时区

var myOffset = -2;

var currentDate = new Date();

var userOffset = currentDate.getTimezoneOffset()/60;

var timeZoneDifference = userOffset - myOffset;

currentDate.setHours(currentDate.getHours() + timeZoneDifference);

document.write("The time and date in Central Europe is: " + currentDate.toLocaleString());

</script>

31 设置日期输出格式

var thisDate = new Date();

var thisTimeString = thisDate.getHours() + ":" + thisDate.getMinutes();

var thisDateString = thisDate.getFullYear() + "/" + thisDate.getMonth() + "/" + thisDate.getDate();

document.write(thisTimeString + " on " + thisDateString);

</script>

32 读取URL参数，你还以为HTML是无状态的么？

var urlParts = document.URL.split("?");

var parameterParts = urlParts[1].split("&");

for (i = 0; i < parameterParts.length; i++) {

var pairParts = parameterParts.split("=");

var pairName = pairParts[0];

var pairValue = pairParts[1];

document.write(pairName + " ：" +pairValue );

}

</script>

33 打开一个新的document对象

function newDocument() {

document.open();

document.write("<p>This is a New Document.</p>");

document.close();

}

</script>

34 页面跳转

window.location = "http://www.liu21st.com/";

</script>

35 添加网页加载进度窗口

<html>

<head>

var placeHolder = window.open('holder.html','placeholder','width=200,height=200');

</script>

</head>

</body>

</html>

avaScript就这么回事3：图像

36 读取图像属性

<a href="#" onClick="window.alert(document.myImage.width)">Width</a>

37 动态加载图像

myImage = new Image;

myImage.src = "Tellers1.jpg";

</script>

38 简单的图像替换

rollImage = new Image;

rollImage.src = "rollImage1.jpg";

defaultImage = new Image;

defaultImage.src = "image1.jpg";

</script>

<a href="/"myUrl"" onMouseOver="document.myImage.src = rollImage.src;"

onMouseOut="document.myImage.src = defaultImage.src;">

39 随机显示图像

var imageList = new Array;

imageList[0] = "image1.jpg";

imageList[1] = "image2.jpg";

imageList[2] = "image3.jpg";

imageList[3] = "image4.jpg";

var imageChoice = Math.floor(Math.random() * imageList.length);

document.write(‘<img src="’ + imageList[imageChoice] + ‘">’);

</script>

40 函数实现的图像替换

var source = 0;

var replacement = 1;

function createRollOver(originalImage,replacementImage) {

var imageArray = new Array;

imageArray[source] = new Image;

imageArray[source].src = originalImage;

imageArray[replacement] = new Image;

imageArray[replacement].src = replacementImage;

return imageArray;

}

var rollImage1 = createRollOver("image1.jpg","rollImage1.jpg");

</script>

<a href="#" onMouseOver="document.myImage1.src = rollImage1[replacement].src;"

onMouseOut="document.myImage1.src = rollImage1[source].src;">

</a>

41 创建幻灯片

var imageList = new Array;

imageList[0] = new Image;

imageList[0].src = "image1.jpg";

imageList[1] = new Image;

imageList[1].src = "image2.jpg";

imageList[2] = new Image;

imageList[2].src = "image3.jpg";

imageList[3] = new Image;

imageList[3].src = "image4.jpg";

function slideShow(imageNumber) {

document.slideShow.src = imageList[imageNumber].src;

imageNumber += 1;

if (imageNumber < imageList.length) {

window.setTimeout("slideShow(" + imageNumber + ")",3000);

}

</script>

</head>

20: <body onLoad="slideShow(0)">

2<img src="/"image1.jpg"" width=100 name="slideShow">

42 随机广告图片

var imageList = new Array;

imageList[0] = "image1.jpg";

imageList[1] = "image2.jpg";

imageList[2] = "image3.jpg";

imageList[3] = "image4.jpg";

var urlList = new Array;

urlList[0] = "http://some.host/";

urlList[1] = "http://another.host/";

urlList[2] = "http://somewh/ere.else/";

urlList[3] = "http://right.here/";

var imageChoice = Math.floor(Math.random() * imageList.length);

document.write(‘<a href="’ + urlList[imageChoice] + ‘"><img src="’ + imageList[imageChoice] + ‘"></a>’);

</script>

avaScript就这么回事4：表单

43 表单构成

<option value="1">First Choice</option>

<option value="2">Second Choice</option>

</select>

<br>

</form>

44 访问表单中的文本框内容

</form>

<a href='#' onClick='window.alert(document.myForm.myText.value);'>Check Text Field</a>

45 动态复制文本框内容

Enter some Text: <input type="text" name="myText"><br>

Copy Text: <input type="text" name="copyText">

</form>

<a href="#" onClick="document.myForm.copyText.value =

document.myForm.myText.value;">Copy Text Field</a>

46 侦测文本框的变化

Enter some Text: <input type="text" name="myText" onChange="alert(this.value);">

</form>

47 访问选中的Select

</select>

</form>

<a href='#' onClick='alert(document.myForm.mySelect.value);'>Check Selection List</a>

48 动态增加Select项

</select>

</form>

document.myForm.mySelect.length++;

document.myForm.mySelect.options[document.myForm.mySelect.length - 1].text = "3";

document.myForm.mySelect.options[document.myForm.mySelect.length - 1].value = "Third Choice";

</script>

49 验证表单字段

function checkField(field) {

if (field.value == "") {

window.alert("You must enter a value in the field");

field.focus();

}

</script>

Text Field: <input type="text" name="myField"onBlur="checkField(this)">

</form>

50 验证Select项

function checkList(selection) {

if (selection.length == 0) {

window.alert("You must make a selection from the list.");

return false;

}

return true;

}

51 动态改变表单的action

Username: <input type="text" name="username"><br>

Password: <input type="password" name="password"><br>

</form>

52 使用图像按钮

Username: <input type="text" name="username"><br>

Password: <input type="password"name="password"><br>

</form>

53 表单数据的加密

<!--

function encrypt(item) {

var newItem = '';

for (i=0; i < item.length; i++) {

newItem += item.charCodeAt(i) + '.';

}

return newItem;

}

function encryptForm(myForm) {

for (i=0; i < myForm.elements.length; i++) {

myForm.elements.value = encrypt(myForm.elements.value);

}

//-->

</SCRIPT>

Enter Some Text: <input type=text name=myField><input type=submit>

20: </form>

JavaScript就这么回事5：窗口和框架

54 改变浏览器状态栏文字提示

window.status = "A new status message";

</script>

55 弹出确认提示框

var userChoice = window.confirm("Click OK or Cancel");

if (userChoice) {

document.write("You chose OK");

} else {

document.write("You chose Cancel");

}

</script>

56 提示输入

var userName = window.prompt("Please Enter Your Name","Enter Your Name Here");

document.write("Your Name is " + userName);

</script>

57 打开一个新窗口

//打开一个名称为myNewWindow的浏览器新窗口

window.open("http://www.liu21st.com/","myNewWindow");

</script>

58 设置新窗口的大小

window.open("http://www.liu21st.com/","myNewWindow",'height=300,width=300');

</script>

59 设置新窗口的位置

window.open("http://www.liu21st.com/","myNewWindow",'height=300,width=300,left=200,screenX=200,top=100,screenY=100');

</script>

60 是否显示工具栏和滚动栏

window.open("http:

61 是否可以缩放新窗口的大小

window.open('http://www.liu21st.com/' , 'myNewWindow', 'resizable=yes' );</script>

62 加载一个新的文档到当前窗口

<a href='#' onClick='document.location = '125a.html';' >Open New Document</a>

63 设置页面的滚动位置

if (document.all) { //如果是IE浏览器则使用scrollTop属性

document.body.scrollTop = 200;

} else { //如果是NetScape浏览器则使用pageYOffset属性

window.pageYOffset = 200;

}</script>

64 在IE中打开全屏窗口

<a href='#' onClick="window.open('http://www.juxta.com/','newWindow','fullScreen=yes');">Open a full-screen window</a>

65 新窗口和父窗口的操作

//定义新窗口

var newWindow = window.open("128a.html","newWindow");

newWindow.close(); //在父窗口中关闭打开的新窗口

</script>

在新窗口中关闭父窗口

window.opener.close()

66 往新窗口中写内容

var newWindow = window.open("","newWindow");

newWindow.document.open();

newWindow.document.write("This is a new window");

newWIndow.document.close();

</script>

67 加载页面到框架页面

</frameset>

在frame1中加载frame2中的页面

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

function doAlert() {

window.alert("Frame 1 is loaded");

}

那么在frame2中可以如此调用该方法

This is frame 2.

</body>

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

var persistentVariable = "This is a persistent value";

</script>

</frameset>

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

</frameset>