Regular Expressions 101

1st Alternative^[^a0\r\n]$

^start of line

Negated Character Class[^a0\r\n]

athe literal a (97₁₀ / 141₈ / 61₁₆) (case sensitive)

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

\ra carriage return (ASCII 13)

\na line-feed (newline) character (ASCII 10)

$end of line

2nd Alternative^[^0\r\n]+[^a\r\n]+$

^start of line

Negated Character Class[^0\r\n]+

+matches at least one character outside the set below:

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

\ra carriage return (ASCII 13)

\na line-feed (newline) character (ASCII 10)

Negated Character Class[^a\r\n]+

+matches at least one character outside the set below:

athe literal a (97₁₀ / 141₈ / 61₁₆) (case sensitive)

\ra carriage return (ASCII 13)

\na line-feed (newline) character (ASCII 10)

$end of line

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

^[^a0\r\n]$|^[^0\r\n]+[^a\r\n]+$

New

a
0
aa
00
0a
a0
1
b
0b
1a
0bb
11a
a1
b0
b0njour
b0njour a
b0njour a toi
attention divisé par 0
est zéro
0 est zéro
0+a
1+b
c0uc0u