Match Function with character +

[Venkat]

Hi,

I am using match function of string to find if a character is there in a
string. The function Match is working fine with all the other characters
except when the searching character is "+".

Here is the piece of code i am using

var line1 = "Hell+O";

if(line1.match("+"))
{
alert("The character is found");
}
In the above code it should alert the statement "The character is found".

Please help me out.
Regards,
Venkat

[Richard Cornford]

"Venkat" <ve*******@yahoo.com> wrote in message
news:1065738057.816453@sj-nntpcache-5...

I am using match function of string to find if a character is
there in a string. The function Match is working fine with all
the other characters except when the searching character is "+".

Here is the piece of code i am using

var line1 = "Hell+O";

if(line1.match("+"))
{
alert("The character is found");
}

In the above code it should alert the statement
"The character is found".

The String.prototype.match method is expecting a regular expression as
its argument. You are passing it a string argument and the ECMA Script
specification does not define behaviour under these circumstances.
However, it is likely (especially if this is working under other
circumstances) that the string is internally being converted into a
regular expression with - new RegExp("+"); - but an unescaped +
character is meaningful to regular expressions and this will not result
in a regular expression that will test for the presence of the +
character in the string.

You might have better luck specifically defining the regular expression
you are passing to the match method as - line1.match( /\+/ ) - , but
regular expressions are relatively heavyweight if the desired task is
just to determine whether a string contains at least one instance of a
single character. String.prototype.indexOf would probably be more
efficient, using a test such as:-

if( line1.indexOf("+") >= 0 ){
alert("")
}

Richard.