What is the best way to first identify and listen for changes in a form

In Angular, there are reactive forms that allow you to track changes in both the complete form and specific fields:

this.filterForm.valueChanges.subscribe(() => {

});

this.filterForm.controls["name"].valueChanges.subscribe(selectedValue => {
});

How can I first listen for changes in the entire form, and then monitor a specific field?

The solution could look something like this:

this.filterForm.valueChanges.subscribe(() => {
    this.filterForm.controls["name"].valueChanges.subscribe(selectedValue => {
    });
});

Answer №1

Give this a shot with RxJs:

this.filterForm.valueChanges.pipe(
   switchMap(() => this.filterForm.controls["name"].valueChanges)
).subscribe(result => {
  // implement your logic here
})

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