How to get the subscribe Class‘s object and original in client?

[lybaiyy123]

var q=new Parse.Query(‘myClass’)
q.subscribe().then(data=>{
console.log(data)
data.on(‘update’,(data2)=>{console.log(data2)})
})

i want know which filed has change

What are the ways to get it?

[dblythy]

var q = new Parse.Query('myClass')
q.subscribe().then(data => {
  data.on('update', (object, original) => {
    const keysChanged = [];
    for (const key of Object.keys(object.toJSON())) {
      if (object.get(key) !== original.get(key)) {
        keysChanged.push(key);
        // you might need further equality testing if object.key is a date or object
      }
    }
    console.log(`keys changed: ${keysChanged.join(',')}`);
  });
});

[lybaiyy123]

thank you very much！