Question

I am working on project where I need to find Frequency from a given text. I wrote a Regular expression that try to detect frequency, however I am stuck with how C# handle it and how exactly I use it in my software

My regular experssion is (\d*)(([,\.]?\s*((k|m)?hz)*)|(\s*((k|m)?hz)*))$

And I am trying to find value from

• 23,2 Hz
• 24,4Hz
• 25,0 Hzsadf
• 26 Hz
• 27Khz
• 28hzzhzhzhdhdwe
• 29
• 30.4Hz
• 31.8 Hz
• 4343.34.234 Khz
• 65SD

Further Explanation:

1. System needs to work for US and Belgium Culture hence, 23.2 (US) = 23,2 (Be)
2. I try to find a Digit, followed by either khz,mhz,hz or space or , or .
3. If it is , or . then it should have another Digit followed by khz, mhz, hz

Any help is appericated.

Answer 1

Running replace

(\d+(?:[.,]\d+)?)\s*([KkMm]?[Hh][Zz])

for ($1 $2) gives

(23,2 Hz)
(24,4 Hz)
(25,0 Hz)sadf
(26 Hz)
(27 Khz)
(28 hz)zhzhzhdhdwe
29
(30.4 Hz)
(31.8 Hz)
4343.(34.234 Khz)
65SD

Any corrections to desired behavior?

upd: this is with negative lookbehind and word boundary:

(?<![.,0-9])(\d+(?:[.,]\d+)?)\s*([KkMm]?[Hh][Zz])\b

(23,2 Hz)
(24,4 Hz)
25,0 Hzsadf
(26 Hz)
(27 Khz)
28hzzhzhzhdhdwe
29
(30.4 Hz)
(31.8 Hz)
4343.34.234 Khz
65SD