FbGadgets

<!-- https://jsfiddle.net/xh61sru9/1/ -->

<div id="TextBox1"></div>

<script>

var eigenschaften = 3;

var eigenschaftsarray = ["b0","b1","b2"];

function buttonClick(e){

if (e.target.tagName.toLowerCase() == "button") {

var btn = e.target;

TextBox1.innerHTML += btn.id

}

}

function dobutton() {

var parent = document.getElementById('TextBox1');

for (i=0; i<eigenschaften; i++){

var btn = document.createElement("button");

btn.id = eigenschaftsarray[i];

btn.innerHTML = eigenschaftsarray[i].split("_").join(" ");          

parent.appendChild(btn);

}

parent.addEventListener("click", buttonClick);

}

dobutton();

</script>

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<div id="TextBox1"></div>
<button id="Btn1">BUTTON1</button>
<button id="Btn2">BUTTON2</button>
<script>
var ButtonIdArray=[Btn1,Btn2];
for(var i = 0; i < ButtonIdArray.length; i++){
ButtonIdArray[i].addEventListener("click",ButtonFunctionName,true);
}
function ButtonFunctionName(event){
TextBox1.innerHTML+=event.target.id
}
</script>
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ABOVE CODE CHANGE INTO BUTTON STRING

1) ALL BUTTON DIVS UNDER TEXTBOX DIV

2) WRITE BUTTON ID ARRAY WITH STRING

3)ADD EVENT LISTNER LINE CHANGE ButtonIdArray[i] INTO TextBox1

if (event.target.tagName.toLowerCase() == "button") 
can change

TextBox1.innerHTML+=event.target.id
if(event.target.id=="TextBox1"){
TextBox1.innerHTML="";
}
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<div id="TextBox1">
<button id="Btn1">BUTTON1</button>
<button id="Btn2">BUTTON2</button>
</div>
<script>
var ButtonIdArray = ["Btn1","Btn2"];
for(var i = 0; i < ButtonIdArray.length; i++){
TextBox1.addEventListener("click",ButtonFunctionName,true);      
}
function ButtonFunctionName(event){
if (event.target.tagName.toLowerCase() == "button") {
TextBox1.innerHTML+=event.target.id
}
}
</script>

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