Call function when button on click

Question

Hi everyone,

Now I writing some JS codes and I've some issues.

I create a text box and button in html as follow:
<input id="txtuname" type="text" name="uname" class="txtbox" />
<input name="btnLogin" type="button" class="btn" value="Login" onclick="chkblank" />

I would like to alert messages by clicking button when the text box is empty text.
So, I wrote follow scripts but it not working.
<script type="text/javascript">
function chkblank(){
var bc=document.getElementsByName("uname");
if (bc.value==""){
alert("Username is blank");
};
}
</script>

Could you please help with some ideas for me?

Thanks.

Ko Dway

Answer 1

://You have missed many things in html anddl css like taking value from tag name but from invalid etc

//solved

<input type="text" id="uname" class="txtbox" />
<input type="button" class="btn" value="Login" onclick="chkblank()" />

<script>
function chkblank(){
var bc=document.getElementById("uname").value;
if (bc==""){
alert("Username is blank");
};
}
</script>

Answer 2

Great!!
I thought the value attribute need to add in if statement.
Thanks a lots and already solved. 😁
Ko Dway