Help! Calling regex's test twice returns opposite results!

[6tr6tr]

If you call the below code, it will incorrectly print "true, false" when it should be "true, true". WHy is that? How do I fix this?

isCapitalLetter = /[A-Z]/g;

//Incorrectly alerts "true,true"
alert( isCapitalLetter.test( "lineHeight" ) + "," + isCapitalLetter.test( "lineHeight" ) );

[sohguanh]

If you call the below code, it will incorrectly print "true, false" when it should be "true, true". WHy is that? How do I fix this?

isCapitalLetter = /[A-Z]/g;

//Incorrectly alerts "true,true"
alert( isCapitalLetter.test( "lineHeight" ) + "," + isCapitalLetter.test( "lineHeight" ) );

I don't know why but if you just use isCapitalLetter = /[A-Z]/; It works ok. I think the g option has a role to play. In most regex, g means to search globally hmmm.......

[Sterling Isfine]

If you call the below code, it will incorrectly print "true, false" when it should be "true, true". WHy is that? How do I fix this?

When you use the g flag, it sets the lastIndex property to mark the position to resume searching. Either don't use the flag or between uses run:

isCapitalLetter.lastIndex = 0

[6tr6tr]

Thanks for the reply. Yes, the problem was the "g". It not only searches globally but caches the last position and saves it across "test" calls.