Extract Date From File Name

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How to split file name for further processing in Power Automate
If you need to extract number or text from the file name, you can use substring method:

invoices_01.2023.xlsx

substring(outputs('Compose'),sub(length(outputs('Compose')),5),5)

substring(triggerOutputs()?['body/{Name}'],sub(length(triggerOutputs()?['body/{Name}']),7),7)

And if there is a date in the end, you can also use split method:

split(substring(triggerOutputs()?['body/{Name}'],sub(length(triggerOutputs()?['body/{Name}']),7),7),'.')

In one Parse Json Action:

{
"file month": "@{split(substring(triggerOutputs()?['body/{Name}'],sub(length(triggerOutputs()?['body/{Name}']),7),7),'.')?[0]}",
"file year": "@{split(substring(triggerOutputs()?['body/{Name}'],sub(length(triggerOutputs()?['body/{Name}']),7),7),'.')?[1]}"
}

{
    "type": "object",
    "properties": {
        "file month": {
            "type": "string"
        },
        "file year": {
            "type": "string"
        }
    }
}

Result: