how can I filter options based on search text in angular

1
votes

I was trying to filter options based on search text in angular.This is the code I am getting value when I search a I get all elements containing a but if I type abc then I shouldn't get the whole array I should get only abc.

filterChanged(filterText: any) {

    const ddd = filterText.target.value
    const test= this.objFlatNodeParrentTempGroup;
    
    const filtered = test.filter((chat) => {
      const searchValue = ddd.toLowerCase();
      return chat.children!.filter((user) => user.item?.toLowerCase().includes(searchValue)).length > 0  ;
    });

    

    this.dataSource.data = filtered;
    this.treeControl.expandAll();

  }
}
angular