setTimout

[Roger Withnell]

Within a function I would like to use a variable in the setTimout string,
for example:

var jHello = 'Hello';
setTimeout("alert(" + jHello + ")", 1000);

This gives jHello undefined error.

What is the correct syntax?

Thanking you in anticipation.

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[VK]

Roger Withnell wrote:

Within a function I would like to use a variable in the setTimout string,
for example:

var jHello = 'Hello';
setTimeout("alert(" + jHello + ")", 1000);

This gives jHello undefined error.

What is the correct syntax?

setTimeout("alert(jHello)", 1000);

setTimeout resolves variables while forming the callBack string. So
1sec later in your variant it will try to execute alert(Hello).

Please note that setTimeout("alert(jHello)", 1000); will fail if jHello
variable declared locally in a function: 1sec later it will not exist
anymore.

[brattn]

or you could evaluate the value of jHello (notice the extra quotes) and
not worry about the scope of jHello:

var jHello = 'Hello';
setTimeout("alert('" + jHello + "')", 1000);
// evaluates to: setTimeout("alert('Hello')",1000);

[Safalra]

On Wed, 8 Mar 2006 14:04:11 -0000, Roger Withnell wrote:

var jHello = 'Hello';
setTimeout("alert(" + jHello + ")", 1000);

This gives jHello undefined error.

Actually it says that 'Hello' (not 'jHello') is undefined, because the
expression becomes setTimeout("alert(Hello)",1000) once the string is
evaluated. I think you meant:

setTimeout("alert('"+jHello+"')",1000);

....which becomes setTimeout("alert('Hello')",1000) once the string is
evaluated (the extra quote marks tell Javascript to treat the contents of
jHello as a string, not a variable).

--
Safalra (Stephen Morley)
http://www.safalra.com/programming/javascript/

[Jonas Raoni]

VK wrote:

Please note that setTimeout("alert(jHello)", 1000); will fail if jHello
variable declared locally in a function: 1sec later it will not exist
anymore.

To solve this problem you can code up this way:

var x = "Joninhas Lalah";
setTimeout(function(){alert(x);}, 0);
--
Now with alcohol <URL:http://youtube.com/watch?v=lnQTZxqxc10> =X
Jonas Raoni Soares Silva
http://www.jsfromhell.com