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Understanding regular expression in javascript

Hi,
I tried the following regex :

/[^"]*/.exec("rohit");
["rohit"]
/([^"]*)/.exec("rohit");
["rohit", "rohit"]

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The second one produces two elements in the array..
I didnt understand the difference between the first and second regex..
As far i understand this should match the first string that does not contain "
But just putting braces the results are different ?

Also

/e/.exec("rohiterohite");
["e"]
/e/g.exec("rohiterohite");
["e"]

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putting /g in front should have done a global match and there should be two e in the array
the non global and global seems to be returning the same output.

what does match = /^"([^"]*)"/.exec(program) do
Looks like it matches a string that starts with " and end with " and in between there are no quotes.
But i tried

var string ="rohit bajaj \" rohit \"bajaj";
/^"([^"]*)"/.exec(string);

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The above returned null.

Please help me understand the correct meaning of the above regular expressions.
Thanks

SOLUTION

Dave Baldwin

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ASKER CERTIFIED SOLUTION

Dan Craciun

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Dan Craciun

@Dave: the OP is most likely using the Console of a browser. Try it in Chrome.

Dan Craciun

/e/g.exec("rohiterohite");

If you want to find the second "e", you'll need to call exec again: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/exec

Basically the regex engine will stop at first match, but will keep the LastIndex value, that will be used on the next run.

Dan Craciun

var string ="rohit bajaj \" rohit \"bajaj";
/^"([^"]*)"/.exec(string);

The null value is what it should return.
The first and last " in var string ="rohit bajaj \" rohit \"bajaj"; are string delimiters. They are not part of the string.

Use this instead:
var string ="\"rohit bajaj \" rohit \"bajaj\"";
/^"([^"]*)"/.exec(string);

SOLUTION

zzynx

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SOLUTION

kaufmed

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Dan Craciun

Thanks kaufmed. Yes, it's "The full string of characters matched".