JavaScript written test questions with answers @20081025_jb51.net_javascript skills

1. Multiple choice questions
1. Which of the following statements will generate a runtime error: (A)
A.var obj = ( );
B.var obj = [ ];
C.var obj = { };
D.var obj = / /;

2. Which of the following words is not a javascript reserved word: (B)
A. with
B. parent
C. class
D. void
3. Please select the expression whose result is true: (C)
A. null instanceof Object
B. null === undefined
C. null == undefined
D. NaN == NaN

2. Indefinite multiple-choice questions
4. Please choose the one with a wrong understanding of javascript: (ABCD)
A. JScript is javascript The abbreviation of
B. JavaScript is a Java scripting language developed by Netscape. Its purpose is to simplify the development of Java
C. The main reason why FireFox and IE have a lot of compatibility problems is that they have limited support for javascript. Support different
D. AJAX technology must use javascript technology
5. The foo object has the att attribute, so to get the value of the att attribute, which of the following methods are possible: (ACE)
A. foo. att
B. foo(“att”)
C. foo[“att”]
D. foo{“att”}
E. foo[“a” ”t” ”t” ]
6. Which HTML tags can be entered manually without specifying special attributes: (AB)
A.
B.
C.
D.

7. Which of the following are global functions of javascript: (ABC)
A. escape
B. parseFloat
C. eval
D. setTimeout
E. alert
8. The correct statements about IFrame are: (ABCD)
A. Through IFrame, web pages can embed other web page content and dynamically change it
B . Under the same domain name, the embedded IFrame can obtain the object of the outer web page
C. Under the same domain name, the outer web page script can obtain the object of the IFrame web page
D. The size of the IFrame can be adjusted through the script
9. The correct expressions about the table are: (ABCDE)
A. The table can contain the TBODY element
B. The table can contain the CAPTION element
C. The table can contain multiple TBODY elements
D. The table can contain the COLGROUP element
E. The table can contain the COL element
10. The correct expressions of IE’s window object are: (ACD)
A. The window.opener attribute itself It points to the window object
B. The window.reload() method can be used to refresh the current page
C. window.location=”a.html” and window.location.href=”a.html” have both functions It is to replace the current page with the a.html page
D. The global variable g is defined; you can use window.g to access the variable

3. Questions and Answers:
1. Talk Discuss the use of the javascript array sorting method sort(), focusing on the use of sort() parameters and its internal mechanism
The function implemented by sort is similar to the JAVA comparator, and the data sorting starts from the first dimension of the multi-dimensional array
You can define your own sorting method, there are not many functions
2. Briefly describe the difference between DIV elements and SPAN elements.
DIV has a carriage return, but SPAN does not.
3. Combined with the structure of text, let’s talk about the difference between innerHTML outerHTML innerText.
You only need to write this question to make it clear
The HTML in the innerHTML object, outerHTML includes the object and the text inside the
innerText object
4. Talk about a few contents of the XHTML specification (at least 3 Article)
Add quotation marks to attributes, and cannot have unmatched tags. Add definitions
5. What relevant knowledge do you know about Web standardization (or website reconstruction)? Briefly describe a few Web standards you know?
W3C standards, etc.
4. Program questions:
1. Complete the content of the foo() function and require a dialog box to pop up to prompt which radio button is currently selected.

2. Function to fill in the comment part body, causing the foo() function call to pop up a "success" dialog box. Code should be kept as short as possible.









function reverse(str) {
// Add code here to complete the string flip function <script> <BR>function foo() { <BR>// 在此处添加代码 <BR>var rg = document.getElementsByName("radioGroup"); <BR>for( var i = 0; i < rg.length; i++ ) <BR>{ <BR>if( rg[i].checked ) <BR>{ <BR>alert("你选择了第" + (i+1) + "个单选框"); <BR>} <BR>} <BR>return false; <BR>} <BR></script>return str.split(",").reverse().join(","); <script> <BR>function foo() { <BR>var str = reverse('a,b,c,d,e,f,g'); <BR>alert(str); <BR>if (str == 'g,f,e,d,c,b,a') alert('成功'); <BR>else alert('失败'); <BR>} <BR>function reverse(str) <BR>{ <BR>// 在此处加入代码，完成字符串翻转功能 <BR>var spl = str.split(','); <BR>var newstr=""; <BR>for(i=spl.length-1;i>=0;i--) <BR>{ <BR>newstr+=spl[i]+','; <BR>} <BR>newstr=newstr.substring(0,newstr.length-1) <BR>return newstr; <BR>} <BR></script> }