allow only csv file selection html accept code example
Example 1: jquery accept only excel file
<input type="file" ID="fileSelect" accept=".xlsx, .xls, .csv"/>
Example 2: html input file type csv
<input id="fileSelect" type="file" accept=".csv, application/vnd.openxmlformats-officedocument.spreadsheetml.sheet, application/vnd.ms-excel" />