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网页制作-JavaScript基础知识:HTML
责任编辑:黄舒奇  发表时间:2007-07-10  最后修改时间2016-05-25
    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

1: <script language=”JavaScript”>
2: JavaScript code goes here
3: </script>

2 隐藏脚本代码

1: <script language=”JavaScript”>
2: <!--
3: document.write(“Hello”);
4: // -->
5: </script>


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: <noscript>
2: Hello to the non-JavaScript browser.
3: </noscript>

4 链接外部脚本文件

1: <script language=”JavaScript” src="/”filename.js"”></script>

5 注释脚本

1: // This is a comment
2: document.write(“Hello”); // This is a comment
3: /*
4: All of this
5: is a comment
6: */

6 输出到浏览器

1: document.write(“<strong>Hello</strong>”);

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

10 字符串替换

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

11 格式化字串

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

12 创建数组

1: <script language=”JavaScript”>
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: </script>

13 数组排序

1: <script language=”JavaScript”>
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: </script>

14 分割字符串

1: <script language=”JavaScript”>
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: </script>

15 弹出警告信息

1: <script language=”JavaScript”>
2: <!--
3: window.alert(“Hello”);
4: // -->
5: </script>

16 弹出确认框

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

17 定义函数

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

18 调用JS函数

1: <a href=”#” onClick=”functionName()”>Link text</a>
2: <a href="/”javascript:functionName"()”>Link text</a>

19 在页面加载完成后执行函数

1: <body onLoad=”functionName();”>
2: Body of the page
3: </body>

20 条件判断

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

21 指定次数循环

1: <script>
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] + “<br>”);
9: }
10: // -->
11: </script>

22 设定将来执行

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

23 定时执行函数

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

24 取消定时执行

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

25 在页面卸载时候执行函数

1: <body onUnload=”functionName();”>
2: Body of the page
3: </body>

JavaScript就这么回事2:浏览器输出

26 访问document对象

1: <script language=”JavaScript”>
2: var myURL = document.URL;
3: window.alert(myURL);
4: </script>

27 动态输出HTML

1: <script language=”JavaScript”>
2: document.write(“<p>Here’s some information about this document:</p>”);
3: document.write(“<ul>”);
4: document.write(“<li>Referring Document: “ + document.referrer + “</li>”);
5: document.write(“<li>Domain: “ + document.domain + “</li>”);
6: document.write(“<li>URL: “ + document.URL + “</li>”);
7: document.write(“</ul>”);
8: </script>

28 输出换行

1: document.writeln(“<strong>a</strong>”);
2: document.writeln(“b”);

29 输出日期

1: <script language=”JavaScript”>
2: var thisDate = new Date();
3: document.write(thisDate.toString());
4: </script>

30 指定日期的时区

1: <script language=”JavaScript”>
2: var myOffset = -2;
3: var currentDate = new Date();
4: var userOffset = currentDate.getTimezoneOffset()/60;
5: var timeZoneDifference = userOffset - myOffset;
6: currentDate.setHours(currentDate.getHours() + timeZoneDifference);
7: document.write(“The time and date in Central Europe is: “ + currentDate.toLocaleString());
8: </script>

31 设置日期输出格式

1: <script language=”JavaScript”>
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: </script>

32 读取URL参数

1: <script language=”JavaScript”>
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: </script>

你还以为HTML是无状态的么?

33 打开一个新的document对象

1: <script language=”JavaScript”>
2: function newDocument() {
3: document.open();
4: document.write(“<p>This is a New Document.</p>”);
5: document.close();
6: }
7: </script>

34 页面跳转

1: <script language=”JavaScript”>
2: window.location = “http://www.liu21st.com/”;
3: </script>

35 添加网页加载进度窗口

1: <html>
2: <head>
3: <script language='javaScript'>
4: var placeHolder = window.open('holder.html','placeholder','width=200,height=200');
5: </script>
6: <title>The Main Page</title>
7: </head>
8: <body onLoad='placeHolder.close()'>
9: <p>This is the main page</p>
10: </body>
11: </html>

JavaScript就这么回事3:图像

36 读取图像属性

1: <img src="/”image1.jpg"” name=”myImage”>
2: <a href=”# ” onClick=”window.alert(document.myImage.width)”>Width</a>
3:

37 动态加载图像

1: <script language=”JavaScript”>
2: myImage = new Image;
3: myImage.src = “Tellers1.jpg”;
4: </script>

38 简单的图像替换

1: <script language=”JavaScript”>
2: rollImage = new Image;
3: rollImage.src = “rollImage1.jpg”;
4: defaultImage = new Image;
5: defaultImage.src = “image1.jpg”;
6: </script>
7: <a href="/”myUrl"” onMouseOver=”document.myImage.src = rollImage.src;”
8: onMouseOut=”document.myImage.src = defaultImage.src;”>
9: <img src="/”image1.jpg"” name=”myImage” width=100 height=100 border=0>

39 随机显示图像

1: <script language=”JavaScript”>
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(‘<img src=”’ + imageList[imageChoice] + ‘“>’);
9: </script>

40 函数实现的图像替换

1: <script language=”JavaScript”>
2: var source = 0;
3: var replacement = 1;
4: function createRollOver(originalImage,replacementImage) {
5: var imageArray = new Array;
6: imageArray[source] = new Image;
7: imageArray[source].src = originalImage;
8: imageArray[replacement] = new Image;
9: imageArray[replacement].src = replacementImage;
10: return imageArray;
11: }
12: var rollImage1 = createRollOver(“image1.jpg”,”rollImage1.jpg”);
13: </script>
14: <a href=”#” onMouseOver=”document.myImage1.src = rollImage1[replacement].src;”
15: onMouseOut=”document.myImage1.src = rollImage1[source].src;”>
16: <img src="/”image1.jpg"” width=100 name=”myImage1” border=0>
17: </a>

41 创建幻灯片

1: <script language=”JavaScript”>
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: </script>
19: </head>
20: <body onLoad=”slideShow(0)”>
21: <img src="/”image1.jpg"” width=100 name=”slideShow”>

42 随机广告图片

1: <script language=”JavaScript”>
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(‘<a href=”’ + urlList[imageChoice] + ‘“><img src=”’ + imageList[imageChoice] + ‘“></a>’);
14: </script>