PUSHLET 实战：JavaScript是否在html完全显示后执行
else if (eventType == 'listen-ack') {_setStatus('listening');_doCallback(event, window.onListenAck);// Send empty heartbeat event. This// silences many busy browser windows.// At least in Moz and IE.alert("在push方式下服务端持续发数据，正常情况下后面的语句继续执行");p_heartbeat();}查看pushlet服务端发送侦听确认后，客户端收到一段内容后（服务端持续发送）是否立刻执行，答案见下：
的几个有争议的地方有：
1：html是否在完全被传送到客户段之后才显示？
2:JavaScript是否在html完全显示后执行？
3：如果JavaScript在html没有被完全显示就可以执行，那么此时的alert会不会是浏览器本身与服务器端的通信处于等待状态？（ alert状态下，浏览器会处于等待状态是指浏览器自身当前的线程处于等待状体）
首先我们先假设html是在完全被传送到客户段之后才显示。那么我们在打开网页的时候也就会有这种现象出现：如果打开很大的网页（指数据比较多，图片很大）时候，刚刚打开的时候会是一片空白，过了一段时间之后画面会突然出现。空白的时候是浏览器在与服务器请求数据，由于数据很大，请求的时间就会相应长。那么在这段时间内由于html数据没有传送完成，浏览器不会显示html的信息，所以会一片空白。
对此我做了一个测试试样：
<div style="padding-right: 5.4pt; padding-left: 5.4pt; background: #e6e6e6 0% 50%; padding-bottom: 4px; width: 98%; padding-top: 4px;">http://www.cnblogs.com/Images/OutliningIndicators/None.gifprivate void Page_Load(object sender, System.EventArgs e)
http://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockStart.gifhttp://www.cnblogs.com/Images/OutliningIndicators/ContractedBlock.gifhttp://www.cnblogs.com/Images/dot.gif{
http://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif for(int i=0;i<50;i++)
http://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gifhttp://www.cnblogs.com/Images/OutliningIndicators/ContractedSubBlock.gif http://www.cnblogs.com/Images/dot.gif{
http://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif this.Page.Response.Write("<table> <tr><td>");
http://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif using (FileStream fs = File.OpenRead(@"D:\Inetpub\wwwroot\Test\123.bmp"))
http://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gifhttp://www.cnblogs.com/Images/OutliningIndicators/ContractedSubBlock.gif http://www.cnblogs.com/Images/dot.gif{
http://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif byte[] b = new byte[1024];
http://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif while (fs.Read(b,0,b.Length) > 0)
http://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockStart.gifhttp://www.cnblogs.com/Images/OutliningIndicators/ContractedSubBlock.gif http://www.cnblogs.com/Images/dot.gif{
http://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif this.Page.Response.Write(b);
http://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockEnd.gif }
http://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockEnd.gif }
http://www.cnblogs.com/Images/OutliningIndicators/InBlock.gif this.Page.Response.Write("</table> </tr></td>");
http://www.cnblogs.com/Images/OutliningIndicators/ExpandedSubBlockEnd.gif }
http://www.cnblogs.com/Images/OutliningIndicators/ExpandedBlockEnd.gif}
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