Help with HTML/Java

Just started to learn HTML/Java. Need to add two text fields for data entry. After user enters the data, need do validation to check if the data entered is a number or not. If it is a number, check if it is in the specified range or not. If it is not a number or the number out of range, pop up a error message.

When testing the code, found that I could not close the alert message. Please help.

http://i19.tinypic.com/6jl84g2.jpg

所有跟帖： 

• HTML code is in this picture -Westmont- ♂ (157 bytes) () 01/07/2008 postreply 18:56:29

• 我测了一下，没问题啊！ -bigcat1969- ♂ (0 bytes) () 01/07/2008 postreply 21:12:59