Learning about JavaScript I have all sorts of problems, which I don't unterstand.
For instance,I found in a program the following:

if (document.all){
var wide = window.screen.availWidth;
var high = window.screen.availHeight;
}

Now.
All the books say that the SYNTAX for IF is

if(condition){
statement(s) if true
}

But in this case it is written

if(document.all).


Is that a condition?


If yes, what condition is it then?
Could anybody give me a hint, please,
what that condition could be?

Thank you!
Jabo

Jabo

the SYNTAX that they book shows is just a prototype for the format, where (condition) is any condition. The snippet that you provided seems to check that the document is loaded [condition will return an object], and then assigns the values to the variables.

: Learning about JavaScript I have all sorts of problems, which I don't unterstand.
: For instance,I found in a program the following:
:
: if (document.all){
: var wide = window.screen.availWidth;
: var high = window.screen.availHeight;
: }
:
: Now.
: All the books say that the SYNTAX for IF is
:
: if(condition){
: statement(s) if true
: }
:
: But in this case it is written
:
: if(document.all).
:
:
: Is that a condition?
:
:
: If yes, what condition is it then?
: Could anybody give me a hint, please,
: what that condition could be?
:
: Thank you!
: Jabo
:
: Jabo
:

: Learning about JavaScript I have all sorts of problems, which I don't unterstand.
: For instance,I found in a program the following:
:
: if (document.all){
: var wide = window.screen.availWidth;
: var high = window.screen.availHeight;
: }
:
: Now.
: All the books say that the SYNTAX for IF is
:
: if(condition){
: statement(s) if true
: }
:
: But in this case it is written
:
: if(document.all).
:
:
: Is that a condition?
:
:
: If yes, what condition is it then?
: Could anybody give me a hint, please,
: what that condition could be?
:
: Thank you!
: Jabo
:
: Jabo
:
Basically, document.all is returning a true or false condition, to see if the document was loaded. if (something) can take any condition as long as it is true or false.