fileupload control file type client verification implementation code_javascript skills

<title>Untitled page</title> <form id="form1" runat="server"> <div> <div id="msg"> </div> <button id="Button1" runat="server" text="上传" enabled="False"></button> <fileupload id="FileUpload1" runat="server" onchange="javascript:CheckFileType();"></fileupload> </div> </form>
[Ctrl A select all Note: If you need to introduce external Js, you need to refresh to execute

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