ASP.NET - Page_Load事件与Page.IsPostBack
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<title>ASP.NET - Page_Load事件与Page.IsPostBack</title>
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Page.IsPostBack 属性
Page_Load 子例程会在页面每次加载时运行。如果您仅希望在页面第一次加载时执行 Page_Load 子例程中的代码,您可以使用 Page.IsPostBack 属性。如果 Page.IsPostBack 属性为 false,则页面第一次被载入,如果为 true,则页面传回服务器(例如,通过点击表单上的按钮):
Sub Page_Load
if Not Page.IsPostBack then
lbl1.Text="The date and time is " & now()
end if
End SubSub Submit(s As Object, e As EventArgs)
lbl2.Text="Hello World!"
End Sub<form runat="server">
<h3><asp教程:label id="lbl1" runat="server" /></h3>
<h3><asp:label id="lbl2" runat="server" /></h3>
<asp:button text="Submit" onclick="submit" runat="server" />
</form>
Page_Load 事件
<script runat="server">
Sub Page_Load
lbl1.Text="The date and time is " & now()
End Sub
</script>
<form runat="server">
<h3><asp:label id="lbl1" runat="server" /></h3>
</form>
Page_Load 事件是众多 ASP.NET 可理解的事件之一。Page_Load 事件会在页面加载时被触发,然后 ASP.NET 会自动调用子例程 Page_Load
<%
lbl1.Text="The date and time is " & now()
%><form runat="server">
<h3><asp:label id="lbl1" runat="server" /></h3>
</form>
</body>
</html>