(转)JavaScript方法和技巧大全

电玩女神 2022-08-25 14:46 166阅读 0赞

转自:http://www.blogercn.com/user9/45360/archives/2006/165379.shtml

JavaScript方法和技巧大全

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  
*第1部分*：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:   
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:   
7: </script>  
  
  
  
10 字符串替换  
  
1: thisVar.replace(“Monday”,”Friday”);  
  
  
11 格式化字串  
  
1: <script language=”JavaScript”>  
2:   
21: </script>  
  
  
  
12 创建数组  
  
1: <script language=”JavaScript”>  
2:   
11: </script>  
  
  
  
13 数组排序  
  
1: <script language=”JavaScript”>  
2:   
11: </script>  
  
  
  
14 分割字符串  
  
1: <script language=”JavaScript”>  
2:   
10: </script>  
  
  
  
15 弹出警告信息  
  
1: <script language=”JavaScript”>  
2:   
5: </script>  
  
  
  
16 弹出确认框  
  
1: <script language=”JavaScript”>  
2:   
5: </script>  
  
  
  
17 定义函数  
  
1: <script language=”JavaScript”>  
2:   
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:   
7: </script>  
  
  
  
21 指定次数循环  
  
1: <script>  
2:   
11: </script>  
  
  
  
22 设定将来执行  
  
1: <script>  
2:   
8: </script>  
  
  
  
23 定时执行函数  
  
1: <script>  
2:   
9: </script>  
  
  
  
24 取消定时执行  
  
1: <script>  
2:   
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>  
  
第2部分：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.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: \*\*\* = “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>  
  
  
  
第3部分：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>  
  
第4 部分：表单  
  
  
还是先继续写完JS就这么回事系列吧～  
43 表单构成  
  
1: <form method=”post” action=”target.html” name=”thisForm”>  
2: <input type=”text” name=”myText”>  
3: <select name=”mySelect”>  
4: <option value=”1”>First Choice</option>  
5: <option value=”2”>Second Choice</option>  
6: </select>  
7: <br>  
8: <input type=”submit” value=”Submit Me”>  
9: </form>  
  
  
44 访问表单中的文本框内容  
  
1: <form name=”myForm”>  
2: <input type=”text” name=”myText”>  
3: </form>  
4: <a href='\#' onClick='window.alert(document.myForm.myText.value);'>Check Text Field</a>  
  
  
45 动态复制文本框内容  
  
1: <form name=”myForm”>  
2: Enter some Text: <input type=”text” name=”myText”><br>  
3: Copy Text: <input type=”text” name=”copyText”>  
4: </form>  
5: <a href=”\#” onClick=”document.myForm.copyText.value =  
6: document.myForm.myText.value;”>Copy Text Field</a>  
  
  
46 侦测文本框的变化  
  
1: <form name=”myForm”>  
2: Enter some Text: <input type=”text” name=”myText” onChange=”alert(this.value);”>  
3: </form>  
  
  
47 访问选中的Select  
  
1: <form name=”myForm”>  
2: <select name=”mySelect”>  
3: <option value=”First Choice”>1</option>  
4: <option value=”Second Choice”>2</option>  
5: <option value=”Third Choice”>3</option>  
6: </select>  
7: </form>  
8: <a href='\#' onClick='alert(document.myForm.mySelect.value);'>Check Selection List</a>  
  
  
48 动态增加Select项  
  
1: <form name=”myForm”>  
2: <select name=”mySelect”>  
3: <option value=”First Choice”>1</option>  
4: <option value=”Second Choice”>2</option>  
5: </select>  
6: </form>  
7: <script language=”JavaScript”>  
8: document.myForm.mySelect.length++;  
9: document.myForm.mySelect.options\[document.myForm.mySelect.length - 1\].text = “3”;  
10: document.myForm.mySelect.options\[document.myForm.mySelect.length - 1\].value = “Third Choice”;  
11: </script>  
  
  
49 验证表单字段  
  
1: <script language=”JavaScript”>  
2: function checkField(field) \{  
3: if (field.value == “”) \{  
4: window.alert(“You must enter a value in the field”);  
5: field.focus();  
6: \}  
7: \}  
8: </script>  
9: <form name=”myForm” action=”target.html”>  
10: Text Field: <input type=”text” name=”myField”onBlur=”checkField(this)”>  
11: <br><input type=”submit”>  
12: </form>  
  
  
50 验证Select项  
  
1: function checkList(selection) \{  
2: if (selection.length == 0) \{  
3: window.alert(“You must make a selection from the list.”);  
4: return false;  
5: \}  
6: return true;  
7: \}  
  
  
51 动态改变表单的action  
  
1: <form name=”myForm” action=”login.html”>  
2: Username: <input type=”text” name=”username”><br>  
3: Password: <input type=”password” name=”password”><br>  
4: <input type=”button” value=”Login” onClick=”this.form.submit();”>  
5: <input type=”button” value=”Register” onClick=”this.form.action = ‘register.html’; this.form.submit();”>  
6: <input type=”button” value=”Retrieve Password” onClick=”this.form.action = ‘password.html’; this.form.submit();”>  
7: </form>  
  
  
52 使用图像按钮  
  
1: <form name=”myForm” action=”login.html”>  
2: Username: <input type=”text” name=”username”><br>  
3: Password: <input type=”password”name=”password”><br>  
4: <input type=”image” src="/”login.gif"” value=”Login”>  
5: </form>  
6:  
  
  
53 表单数据的加密  
  
1: <SCRIPT LANGUAGE='JavaScript'>  
2:   
17: </SCRIPT>  
18: <form name='myForm' onSubmit='encryptForm(this); window.alert(this.myField.value);'>  
19: Enter Some Text: <input type=text name=myField><input type=submit>  
20: </form>  
  
  
  
  
第5部分：窗口和框架  
  
  
54 改变浏览器状态栏文字提示  
  
1: <script language=”JavaScript”>  
2: window.status = “A new status message”;  
3: </script>  
  
  
55 弹出确认提示框  
  
1: <script language=”JavaScript”>  
2: var userChoice = window.confirm(“Click OK or Cancel”);  
3: if (userChoice) \{  
4: document.write(“You chose OK”);  
5: \} else \{  
6: document.write(“You chose Cancel”);  
7: \}  
8: </script>  
  
  
56 提示输入  
  
1: <script language=”JavaScript”>  
2: var userName = window.prompt(“Please Enter Your Name”,”Enter Your Name Here”);  
3: document.write(“Your Name is “ + userName);  
4: </script>  
  
  
57 打开一个新窗口  
  
1: //打开一个名称为myNewWindow的浏览器新窗口  
2: <script language=”JavaScript”>  
3: window.open(“http://www.liu21st.com/”,”myNewWindow”);  
4: </script>  
  
  
58 设置新窗口的大小  
  
1: <script language=”JavaScript”>  
2: window.open(“http://www.liu21st.com/”,”myNewWindow”,'height=300,width=300');  
3: </script>  
  
  
59 设置新窗口的位置  
  
1: <script language=”JavaScript”>  
2: window.open(“http://www.liu21st.com/”,”myNewWindow”,'height=300,width=300,left=200,screenX=200,top=100,screenY=100');  
3: </script>  
  
  
60 是否显示工具栏和滚动栏  
  
1: <script language=”JavaScript”>  
2: window.open(“http:  
  
  
61 是否可以缩放新窗口的大小  
  
1: <script language=”JavaScript”>  
2: window.open('http://www.liu21st.com/' , 'myNewWindow', 'resizable=yes' );</script>  
  
  
62 加载一个新的文档到当前窗口  
  
1: <a href='\#' onClick='document.location = '125a.html';' >Open New Document</a>  
  
  
63 设置页面的滚动位置  
  
1: <script language=”JavaScript”>  
2: if (document.all) \{ //如果是IE浏览器则使用scrollTop属性  
3: document.body.scrollTop = 200;  
4: \} else \{ //如果是NetScape浏览器则使用pageYOffset属性  
5: window.pageYOffset = 200;  
6: \}</script>  
  
  
64 在IE中打开全屏窗口  
  
1: <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  
  
1: <script language=”JavaScript”>  
2: //定义新窗口  
3: var newWindow = window.open(“128a.html”,”newWindow”);  
4: newWindow.close(); //在父窗口中关闭打开的新窗口  
5: </script>  
6: 在新窗口中关闭父窗口  
7: window.opener.close()  
  
  
66 往新窗口中写内容  
  
1: <script language=”JavaScript”>  
2: var newWindow = window.open(“”,”newWindow”);  
3: newWindow.document.open();  
4: newWindow.document.write(“This is a new window”);  
5: newWIndow.document.close();  
6: </script>  
  
  
67 加载页面到框架页面  
  
1: <frameset cols=”50%,\*”>  
2: <frame name=”frame1” src="/”135a.html"”>  
3: <frame name=”frame2” src="/”about:blank"”>  
4: </frameset>  
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: <body onLoad=”parent.frame1.doAlert();”>  
2: This is frame 2.  
3: </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  
  
1: <script language=”JavaScript”>  
2: var persistentVariable = “This is a persistent value”;  
3: </script>  
4: <frameset cols=”50%,\*”>  
5: <frame name=”frame1” src="/”138a.html"”>  
6: <frame name=”frame2” src="/”138b.html"”>  
7: </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  
  
1: <frameset cols=”0,50%,\*”>  
2: <frame name=”codeFrame” src="/”140code.html"”>  
3: <frame name=”frame1” src="/”140a.html"”>  
4: <frame name=”frame2” src="/”140b.html"”>  
5: </frameset>*