A great function for any kind of text extraction. I mainly use it for HTML. I write it a LOT so here it is!

selectin.js

function selectin(str, startstr, endstr) {
    const starti = str.indexOf(startstr) + startstr.length
    if (starti == -1) return -1
    const endi = str.indexOf(endstr, starti)
    if (endi == -1) return -1
    return str.substring(starti, endi)
}

function selectinall(str, startstr, endstr) {
    let result = []
    let starti = 0

    while (starti < str.length) {
        const startIndex = str.indexOf(startstr, starti)
        if (startIndex == -1) break

        const endIndex = str.indexOf(endstr, startIndex + startstr.length)

        if (endIndex == -1) break

        const selectedText = str.substring(startIndex + startstr.length, endIndex)
        result.push(selectedText)

        starti = endIndex + endstr.length
    }

    return result
}