檢查一個字符串是否以使用正則表達式的數字開頭

Question

如果一行以03:32:33（時間戳）之類的數字開頭，我正在匹配時正在寫入filebeat配置。我目前正在做 -

\d 

但它沒有得到承認，有什麼我應該做的。我不是特別好/有正則表達式的經驗。幫助將不勝感激。

Answer 1

真正的問題是filebeatdoes not support \d。

替換\d通過[0-9]您的正則表達式將工作。

我建議你看看filebeat的Supported Patterns。

此外，請確定您使用的是^，它代表字符串的開頭。

Answer 2

Regex: (^\d) 

1st Capturing group (^\d) 
    ^Match at the start of the string 
    \d match a digit [0-9] 

Answer 3

您可以使用：

^\d{2}:\d{2}:\d{2} 

字符^一行的開頭匹配。

Answer 4

你可以使用這個表達式：

^([0-9]{2}:?){3}

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DEMO

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Assert position at the beginning of the string «^» 
Match the regex below and capture its match into backreference number 1 «([0-9]{2}:?){3}» 
    Exactly 3 times «{3}» 
     You repeated the capturing group itself. The group will capture only the last iteration. Put a capturing group around the repeated group to capture all iterations. «{3}» 
     Or, if you don’t want to capture anything, replace the capturing group with a non-capturing group to make your regex more efficient. 
    Match a single character in the range between 「0」 and 「9」 «[0-9]{2}» 
     Exactly 2 times «{2}» 
    Match the character 「:」 literally «:?» 
     Between zero and one times, as many times as possible, giving back as needed (greedy) «?»