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Martin Coutts
18,154 Pointsfilter array in React
I have 2 arrays, a list of countries and then a list of football competitions. The goal is that the user will select the country from a select. Once this happens the id of that country is fed to state, I have got this working. Once the state has changed I want to execute a function which will filter through the competitions and gather all of the ones with the same area code.
handleCountrySelect = value => {
this.setState({ selectedCountryId: value }, () =>
this.filterCompetitions()
);
console.log(value);
};
filterCompetitions = () => {
let selectedCountryId = this.state.selectedCountryId;
let filteredCompetitions = this.state.competitions.filter(function(
competition
) {
return competition.area.id === selectedCountryId;
});
console.log(selectedCountryId);
console.table(this.state.competitions);
console.log(filteredCompetitions);
};
If I give it an id that matches it works, however when I try to use the selectedCountryId variable it just returns an empty array even though the variable is correct.
1 Answer
Margareta György
7,212 PointsHello :) maybe you already got it working. If not try something like this: You don't have to put the filtering inside a function, you could just have it in render()
```let filteredCompetitions = this.state.competitions && this.state.competitions.filter(competition => competition.area.id === selectedCountryId)
```