How can I use regex

[taqy (Mohammed taqy)]

how can I use the regex ?
Please Help

[dora_paz (Dora)]

You could use regex extension by @Kevinkun

Many examples can be found in

RegExr: Learn, Build, & Test RegEx

[dora_paz (Dora)]

What exactly do you want to achieve using regex ?

[TimAi2 (metricrat)]

Also, and extension by @Kevinkun

Regular Expression Extension

[dora_paz (Dora)]

@dora_paz

You could use regex extension by @Kevinkun

Already mentioned

[taqy (Mohammed taqy)]

i will use regex to accept or not accept the UserName like instagram UserName

[dora_paz (Dora)]

Let assume that you want your username to contain only a-z 0-9 and . then you can check like this