js-face question 1

Values of 1, y, and z?
var x = 1;
var y = 0;
var z = 0;
function Add (n) {n=n+1;}
y = Add (x);
function Add (n) {n=n+3;}
z = Add (x);
Y,z Output Undefind
Note: The function does not return a value, the default is Undefind;

2, JS is Object-oriented, how to embody the inheritance relationship JS?
Use prototype to implement

3, how to JS disable checkbox
var box = document.getElementById ("box"); Js
Box.disabled = true;
Jq
$ ("#box"). attr ("Disabled", true);

4, ReadOnly and disabled
ReadOnly is valid for input (Text/possword) and textarea, data can be transmitted
Disabled applies to all form elements, and data is not transportable

5, JS in the 3 kinds of pop-up message reminders (Warning window, confirmation window, information Input window) of the command-type what
Alert ("A");
Confirm ("B");
If the user clicks the OK button, confirm () returns TRUE. If you click the Cancel button, confirm () returns false.
Prompt ("Please enter", "Zhang San");
Prompt (Text,defaulttext)
Text is optional. Plain text to display in the dialog box (instead of HTML-formatted text)
DefaultText is optional. The default input text

6, write Datedemo return results, system time assumed to be today
function Datedemo () {
var d,s = "Today's date is:";
D = new Date ();
s + = D.getmonth () +1+ "/";
s + = D.getdate () + "/";
s + = D.getfullyear () + "/";
return s;
}
Console.log (Datedemo ());

7. The result of operation?
For (i=0, j=0; i<10, j<6; i++, J + +) {
K = i + j;
Console.log (i + "-" +j);
}
Console.log (k + "--------"); 10

8. The result of operation?
var a = "0";
Console.log (typeof (a));
if (a) {
Console.log ("true");
}else{
Console.log ("false");
}
True

The object model (BOM) of the browser?
Window
Window.alert ();
Window.prompt ();
Window.confirm ();
window.open ();
Window.close ();

Document
document.write ();

History//When your users browse the Web, the BOM holds a recent access list, and history is the object
History.back (); Hind legs
History.forward (); Forward
History.go (n); Positive progression, negative hind legs

Location
Location.href
Location.host//Return Web site + port

Screen
Used to display the size and color of a Web page display
Screen.width/screen.height; Represents the resolution of the monitor (total width, height)

8. What are the common objects of JavaScript (DOM)
String (), Math (), Date (), Array ();

9, the difference between innerhtml,innertext,outerhtml?
InnerHTML The output element contains the code + text information;
InnerText the text information contained in the output element;
outerHTML Output contains elements

js-face question 1