在onClick方法上，我不能两次使用.push

Question

I'm trying to go through a list of employees and when I click a button it adds their employee ID in an array. I try to do this with a .push method onto the array, but it only works once, and then when I try to push the button for the next employee it says .push is not a function.

constructor(props:any){
    super(props);
    this.state={
        employees:[{name: 'joe', id: 12345},{name: 'kelly', id: 12321},{name: 'Jessica', id: 12255},{name: 'Paul', id: 98798}],
        ids:[],
        badgeID: '',
        currentEmployee: null
    }
}


check = () => {
    const {ids, badgeID, employees} = this.state

    let filteredEmployee = employees.filter(employee => {
        return employee.id === Number(badgeID)
    })

    this.setState({
        currentEmployee: filteredEmployee,
        drinkModal: true,
        ids: ids.push(badgeID)
    })
    console.log('ids', this.state.ids)
}


handleChange = (e: any, type: string) => {
    if(type === 'badge'){
        this.setState({badgeID: e.target.value})
    }
}

render(){
    return(
        <TextField onChange={e => this.handleChange(e, 'badge')}/>
        <Button onClick={this.check}>Add Employee</Button>
)}

Answer 1

You are doing:

ids: ids.push(badgeID)

This saves the return value of the push method which is not an array, so the next time you call push it fails. Instead you need to do something like:

ids: [...ids, badgeID]

or:

ids: ids.concat([badgeId])

Answer 2

This is because ids.push returns the length of the new array: check the docs

Basically you are setting to ids an integer value.