var arr = contentPane.getWidgetsByName("qty");
for (var i = 0; i < arr.length; i++) {
arr[i].setValue("");
}
=======
contentPane.setCellValue(sheet号,列号,行号,值); //sheet号行号列号是从0开始
你是单元格,要改成设置单元格值
var arr = contentPane.getWidgetsByName("qty");
for (var i = 0; i < arr.length; i++) {
contentPane.setCellValue(0,8,2+i,"");
}