js usage methods and functions summary_javascript skills

A summary of how to use js is quite good. It is good for both novices and veterans.

1 Create script block
1:
2 Hidden script code
1:
Relevant code will not be executed in browsers that do not support JavaScript
3 Displayed when the browser does not support it
1:
4 Link to external script file
1:
5 Comment script
1: // This is a comment
2: document.write("Hello"); // This is a comment
3: /*
4: All of this
5: is a comment
6: */
6 Output to browser
1: document.write("Hello");
7 Define variables
1: var myVariable = "some value";
8 String addition
1: var myString = "String1" "String2";
9 characters String search
1:
10 String replacement
1: thisVar.replace("Monday","Friday");
11 Format string
1:
12 Create array
1: < ;script language="JavaScript">
2:
11:
13 Array sorting
1:
14 Split string
1:
15 Pop-up warning message
1:
17 Define function
1:
27 Dynamically output HTML
1:
28 Output newline
1: document.writeln("a");
2: document.writeln("b");
29 Output date
1:
31 Set date output format
1:
32 Read URL parameters
1:
Do you still think HTML is stateless?
33 Open a new document object
1:
34 page jump
1:
35 Add web page loading progress window
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9:

This is the main page

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36 Read image attributes
1:
2: Width
3:
37 Dynamically loading images
1:
38 Simple image replacement
1:
7: 8: onMouseOut="document.myImage.src = defaultImage.src;">
9:
39 Randomly display images
1:
40 Image replacement implemented by function
1:
14: 15: onMouseOut="document.myImage1.src = rollImage1[source].src;"> ;
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41 Create slideshow
1:
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42 随机广告图片
1:

43 表单构成
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2:
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4: First Choice
5: Second Choice
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44 访问表单中的文本框内容
1:

2:
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4: Check Text Field
45 动态复制文本框内容
1:

2: Enter some Text:

3: Copy Text:
4:

5: Copy Text Field
46 侦测文本框的变化
1:

2: Enter some Text:
3:

47 访问选中的Select
1:

2:
3: 1
4: 2
5: 3
6:
7:

8: Check Selection List
48 动态增加Select项
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2:
3: 1
4: 2
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49 验证表单字段
1:
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10: Text Field:
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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:

2: Username:

3: Password:

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52 使用图像按钮
1:

2: Username:

3: Password:

4:
5:

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53 表单数据的加密
1:
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19: Enter Some Text:
20: