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Javascript - How to program a click counter?

开发者 https://www.devze.com 2022-12-12 10:55 出处：网络

I have tried before, but it doesn\'t work. Is it any wrongs of the开发者_如何学C code? <script type =\"text/javascript\">

相关专题：button javascript

I have tried before, but it doesn't work. Is it any wrongs of the开发者_如何学C code?

<script type ="text/javascript">
function count()
{
var x = 0;
x += 1;
document.getElementById( "counting" ).value = x;
}
</script>
</head>
<body>

<input type ="button" value = "Click" onclick = "count()"/><br><br>
<input id = "counting" type = "text" />

</body>

you need to move the line var x = 0; to somewhere outside of the function count in order for it to be in the global scope. This means that changes made to it by the function count will persist.

e.g.

var x = 0;
function count() {
    x += 1;
    document.getElementById( "counting" ).value = x;
}

X appears to be declared as a local variable, so it's going to be reset to zero every time the function is called. Try moving "var x = 0;" outside the function (into global scope).

You are initializing x to 0 every time the button is clicked. Try var x=0; outside the function.