Addeventlistener with ajax not working well

Question

I want to show the content of a txt file inside a \'div\', so I\'m calling my function with a button, but the functions triggers even if I don\'t push the button, here\'s my

Answer 1

You are calling a function instead of passing in as a anonymous method.

window.onload=function(){
    document.getElementById("showF").addEventListener("click" , function(){
        sacardatos('P1.txt','container');
    },false);
}

Answer 2

The second argument to addEventListener should be a function. You're not passing a function, you're calling the function immediately and passing the result. Change to:

document.getElementById("showF").addEventListener("click", function() {
    sacardatos('P1.txt','container');
}, false);