在HTML标记内调用javascript函数

Question

I have the following.

<a href="#" onclick="hello()">click me</a>

And I have a Javascript file

$(document).ready(function() {
  function hello() {
    alert('hi');
  }
});

But when I click on "click me", the alert is not being fired. It says "hello" is not defined. I remove document.ready, and it works.

Is this because "hello" is not being defined until the entire document is ready, but when the above "anchor" tag is being rendered, it can't find the function?

Is there any way I can get this to work?

• I have to call javascript function from the html tag via ugly "onclick"
• I need to keep my JS inside document.ready (there are other parts I need)

Answer 1

您还可以在Anchor Tag中使用HREF属性和javascript： keyword来调用JavaScript函数：

<a href="javascript:hello()">click me</a>

Answer 2

Your hello() function declaration is not in the global scope so the call from the HTML which is trying to call it at the global scope can't find it. You can either fix it by moving your hello() function into the global scope:

function hello() {
    alert('hi');
}

$(document).ready(function() {
});

or by declaring it at the global scope:

$(document).ready(function() {
  window.hello = function() {
    alert('hi');
  }
});

Answer 3

1. Remove "hello()" from $(document).ready() callback.
2. Call the "hello()" in a "click" event callback.

<a href="#" id="say_hello">click me</a>

<script type="text/javascript">
$(document).ready(function() {
    $('#say_hello').click(function() {
        hello();
    });
});

function hello() {
    alert('hi');
}
</script>

Answer 4

The reason hello is undefined is because Hello() only exists in the context of the DomReady callback. You need to define Hello() in the global context.