In order to prevent malicious attempts to obtain verification text messages and verification emails, the website will have a countdown effect on the button that clicks to obtain the verification code. To implement this function, a setInterval and a clearInterval can be used, and it does not require too much code. The example effects and codes are as follows:
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<input type="button" style="height:32px;width:120px;" value="点击发送验证码" onclick="sendCode(this)" />
<script type="text/javascript">
var clock = '';
var nums = 10;
var btn;
function sendCode(thisBtn)
{
btn = thisBtn;
btn.disabled = true; //将按钮置为不可点击
btn.value = nums+'秒后可重新获取';
clock = setInterval(doLoop, 1000); //一秒执行一次
}
function doLoop()
{
nums--;
if(nums > 0){
btn.value = nums+'秒后可重新获取';
}else{
clearInterval(clock); //清除js定时器
btn.disabled = false;
btn.value = '点击发送验证码';
nums = 10; //重置时间
}
}
</script>
Use setInterval and clearIntervaljs to achieve the countdown effect of js click to obtain verification code. I hope it will be helpful to everyone's learning.
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