<asp:Button runat="server" ID="btn" Text="免费获取验证码" onclick="btn_Click" />
js:
<script type="text/javascript"> var wait = 6; function time() { if (wait == 0) { document.getElementById("btn").removeAttribute("disabled"); document.getElementById("btn").value = "免费获取验证码"; wait = 6; } else { document.getElementById("btn").setAttribute("disabled", true); document.getElementById("btn").value = wait + "秒后可以重新发送"; wait--; setTimeout(function () { time() }, 1000) } } </script>
后台页面加载时调用js
protected void Page_Load(object sender, EventArgs e) { if (!IsPostBack) { ClientScript.RegisterStartupScript(GetType(), "js", "time()", true); } }
效果图: