How to add onClick to button tag in Javascipt-CodePudding

I would like to create a button using Javascript but why does the upB.onClick = testUp() not work?

<button  onClick="testUp()">Up</button>

var upB = document.createElement('button');
upB.classList.add("up_btn");
upB.innerText = "Up";
upB.onClick = testUp();

CodePudding user response：

I would use upB.setAttribute('onclick','testUp()') ;

var upB = document.createElement('button');
upB.classList.add("up_btn");
upB.innerText = "Up";
upB.setAttribute('onclick','testUp()') ;
document.body.appendChild(upB);

function testUp(){alert('testUp')}

EDIT : following suggestion in comment, please see snippet below with addEventListener.

var upB = document.createElement('button');
upB.classList.add("up_btn");
upB.innerText = "Up";
upB.addEventListener("click", testUp, false);
document.body.appendChild(upB);

function testUp(){alert('testUp')}

CodePudding user response：

var upB = document.createElement('button');
upB.classList.add("up_btn");
upB.innerText = "Up";
upB.addEventListener("click", testUp);

Try This