Just use a regex. I am going to assume that you are using a perl script of some kind. 


[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\
+xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\
xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:(?:[^(\040)
+<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(
\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|"[^\\\x80-\xff\n\015"]*(?:\\[^
+\x80-\xff][^\\\x80-\xff\n\015"]*)*")[\04
0\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\
+n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\
n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:\.[\040\t]*(?:\
+([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\
xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*
+)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]
*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\
+[\]\000-\037\x80-\xff])|"[^\\\x80-\xff\n
\015"]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015"]*)*")[\040\t]*(?:\([^\\\x
+80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\(
[^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^
+\\\x80-\xff\n\015()]*)*\)[\040\t]*)*)*@[
\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\x
+ff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\x
ff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,
+;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040
)<>@,;:".\\\[\]\000-\037\x80-\xff])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^
+\x80-\xff])*\])[\040\t]*(?:\([^\\\x80-\x
ff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-
+\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x8
0-\xff\n\015()]*)*\)[\040\t]*)*(?:\.[\040\t]*(?:\([^\\\x80-\xff\n\015(
+)]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\
n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\
+015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:"
.\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff
+])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x8
0-\xff])*\])[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|
+\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xf
f][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*)*
+|(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-
\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|"[^\\\x80-\xff\n\0
+15"]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\01
5"]*)*")[^()<>@,;:".\\\[\]\x80-\xff\000-\010\012-\037]*(?:(?:\([^\\\x8
+0-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([
^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\
+\\x80-\xff\n\015()]*)*\)|"[^\\\x80-\xff\
n\015"]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015"]*)*")[^()<>@,;:".\\\[\]\
+x80-\xff\000-\010\012-\037]*)*<[\040\t]*
(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015
+()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015
()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:@[\040\t]*(?:\([^\\\
+x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\
([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[
+^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:
[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\00
+0-\037\x80-\xff])|\[(?:[^\\\x80-\xff\n\0
15\[\]]|\\[^\x80-\xff])*\])[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:
+\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*
(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*
+\)[\040\t]*)*(?:\.[\040\t]*(?:\([^\\\x80
-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x
+80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\
\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x
+80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\
037\x80-\xff])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80-\xff])*\])[\040\
+t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[
^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\
+015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[
\040\t]*)*)*(?:,[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\x
+ff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80
-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*
+)*@[\040\t]*(?:\([^\\\x80-\xff\n\015()]*
(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x8
+0-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015
()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(
+\040)<>@,;:".\\\[\]\000-\037\x80-\xff])|
\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80-\xff])*\])[\040\t]*(?:\([^\\\x8
+0-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([
^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\
+\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:\.
[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\
+xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\
xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@
+,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\04
0)<>@,;:".\\\[\]\000-\037\x80-\xff])|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[
+^\x80-\xff])*\])[\040\t]*(?:\([^\\\x80-\
xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80
+-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x
80-\xff\n\015()]*)*\)[\040\t]*)*)*)*:[\040\t]*(?:\([^\\\x80-\xff\n\015
+()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff
\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n
+\015()]*)*\)[\040\t]*)*)?(?:[^(\040)<>@,
;:".\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\
+xff])|"[^\\\x80-\xff\n\015"]*(?:\\[^\x80
-\xff][^\\\x80-\xff\n\015"]*)*")[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(
+?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\01
5()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015(
+)]*)*\)[\040\t]*)*(?:\.[\040\t]*(?:\([^\
\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\
+\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\)
)[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\
+037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\
000-\037\x80-\xff])|"[^\\\x80-\xff\n\015"]*(?:\\[^\x80-\xff][^\\\x80-\
+xff\n\015"]*)*")[\040\t]*(?:\([^\\\x80-\
xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80
+-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x
80-\xff\n\015()]*)*\)[\040\t]*)*)*@[\040\t]*(?:\([^\\\x80-\xff\n\015()
+]*(?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n
\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\0
+15()]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".
\\\[\]\000-\037\x80-\xff]+(?![^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]
+)|\[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80
-\xff])*\])[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\
+([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff
][^\\\x80-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015()]*)*\)[\040\t]*)*(?:
+\.[\040\t]*(?:\([^\\\x80-\xff\n\015()]*(
?:(?:\\[^\x80-\xff]|\([^\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80
+-\xff\n\015()]*)*\))[^\\\x80-\xff\n\015(
)]*)*\)[\040\t]*)*(?:[^(\040)<>@,;:".\\\[\]\000-\037\x80-\xff]+(?![^(\
+040)<>@,;:".\\\[\]\000-\037\x80-\xff])|\
[(?:[^\\\x80-\xff\n\015\[\]]|\\[^\x80-\xff])*\])[\040\t]*(?:\([^\\\x80
+-\xff\n\015()]*(?:(?:\\[^\x80-\xff]|\([^
\\\x80-\xff\n\015()]*(?:\\[^\x80-\xff][^\\\x80-\xff\n\015()]*)*\))[^\\
+\x80-\xff\n\015()]*)*\)[\040\t]*)*)*>)

[download]
And also check out this for other Common Regex's

LeGo

In reply to RE: Email validation by LeGo
in thread Email validation by Anonymous Monk

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