How to call specific Object from ObjectArray

Trying to get e.target.data from the objects generated. console.log displays they have props with the data value I assigned them with. How are event specific objects called? I need to access the original value and also want to onClick delete them. But so far everything i tried, only returns _this2 TypeError (is not a function), or data i tried to pass with the onClick handler wasn't passed. this.props.plz_zwischenis a simple array of strings and passed from parent Component.

import React, { Component } from 'react';

export default class checkBox extends Component {

    constructor(){
        super();

        this.state = {
            checkboxState: false
        };
        this.toggle = this.toggle.bind(this);
    }
    toggle(e){
        console.log('toggle was triggered');
    }

    render(){

        let miniBox = this.props.plz_zwischen.map(function(a, index){
            return <li key={index} data={a}> <label> {a} </label> <input type="checkbox"  onClick={(e) => this.toggle()} /></li>;
        });

        return(
            <div>
                <ul id="rowlist">
                    {miniBox}
                </ul>
            </div>
        );
    }
}