如何检测单元格在Ext JS中是否被修改？

grid.on('beforeedit', function(editor, context) {
  var record = context.record;
  var fieldName = context.field;
  var originalValue = record.get(fieldName);
  var newValue = context.value;

  if (originalValue !== newValue) {
    // 单元格被修改
    console.log('单元格被修改');
  }
});

grid.on('edit', function(editor, context) {
  var record = context.record;
  var fieldName = context.field;
  var originalValue = record.get(fieldName);
  var newValue = context.value;

  if (originalValue !== newValue) {
    // 单元格被修改
    console.log('单元格被修改');
  }
});