How can I import multiple CSVs to preset sheets?

Question

I have some CSV files on my G-drive that I want to import to preset sheets, based on file names. For example,

1. I have CSV files named: "REP1-abc", "REP2-bcd", "REP3-cde",...
2. I have spreadsheet with sheets named: "REP1", "REP2", "REP3",...

Target is to take first four letters of file name to match correct sheet name and import it to that sheet. Im new in this so i will appreciate any tips on how to compare those two names.

Answer 1

Loading CSVs

function loadcsvs() {
  const fldr = DriveApp.getFolderById("Folder id");
  const files = fldr.getFileByType(MimeType.CSV);
  const ss = SpreadsheetApp.getActive();
  const shts = ss.getSheets().map(sh => sh.getName());
  while(files.hasNext()) {
    let file = files.next();
    let sname = file.getName().slice(0,4);
    let idx = shts.indexOf(sname);
    if(~idx) {
      let sht = ss.getSheetByName(shts[idx]);
      let vs = Utilities.parseCsv(file.getBlob().getDataAsString())
      sht.getRange(1,1,vs.length,vs[0].length).setValues(vs);
    }
  }
}