echo "<a href='phpwan.php?pageno=($pageno+1)'>下一页<a> ";

本来就是这样啊，你应该写成。

echo "<a href='phpwan.php?pageno=" . ($pageno+1) . "'>下一页</a>"

错的地方多了，改成下面的：

$main = "网上大名：<a href='mailto:".$email."'>".$nickname."</a>:(".$t.")<br>留言： ".$note."<br><hr>"

所需材料：食盐、淀粉、洗衣粉、冷水。

一、往床单上有经血的地方放一勺淀粉。

/iknow-pic.cdn.bcebos.com/5366d0160924ab18a49d49123afae6cd7b890b0f"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/5366d0160924ab18a49d49123afae6cd7b890b0f?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="https://iknow-pic.cdn.bcebos.com/5366d0160924ab18a49d49123afae6cd7b890b0f"/>

二、用手轻轻抹均匀。

/iknow-pic.cdn.bcebos.com/0eb30f2442a7d933f5234c56a24bd11373f0010f"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/0eb30f2442a7d933f5234c56a24bd11373f0010f?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="https://iknow-pic.cdn.bcebos.com/0eb30f2442a7d933f5234c56a24bd11373f0010f"/>

三、再倒一点食用盐。

/iknow-pic.cdn.bcebos.com/80cb39dbb6fd5266e0a09431a418972bd407360f"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/80cb39dbb6fd5266e0a09431a418972bd407360f?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="https://iknow-pic.cdn.bcebos.com/80cb39dbb6fd5266e0a09431a418972bd407360f"/>

四、蘸一点冷水。

/iknow-pic.cdn.bcebos.com/a5c27d1ed21b0ef43efe0d7bd2c451da81cb3e84"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/a5c27d1ed21b0ef43efe0d7bd2c451da81cb3e84?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="https://iknow-pic.cdn.bcebos.com/a5c27d1ed21b0ef43efe0d7bd2c451da81cb3e84"/>

五、倒上适量洗衣粉。

/iknow-pic.cdn.bcebos.com/7a899e510fb30f247b874626c795d143ad4b03f1"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/7a899e510fb30f247b874626c795d143ad4b03f1?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="https://iknow-pic.cdn.bcebos.com/7a899e510fb30f247b874626c795d143ad4b03f1"/>

六、再次用手抹均匀。

/iknow-pic.cdn.bcebos.com/a8773912b31bb051a354260d397adab44aede0a7"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/a8773912b31bb051a354260d397adab44aede0a7?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="https://iknow-pic.cdn.bcebos.com/a8773912b31bb051a354260d397adab44aede0a7"/>

七、反复地用手揉搓。

/iknow-pic.cdn.bcebos.com/d058ccbf6c81800ae4f4232bbe3533fa828b4786"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/d058ccbf6c81800ae4f4232bbe3533fa828b4786?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="https://iknow-pic.cdn.bcebos.com/d058ccbf6c81800ae4f4232bbe3533fa828b4786"/>

八、最后浸入水中清洗。

/iknow-pic.cdn.bcebos.com/e7cd7b899e510fb3380fe2b2d633c895d1430c84"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/e7cd7b899e510fb3380fe2b2d633c895d1430c84?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="https://iknow-pic.cdn.bcebos.com/e7cd7b899e510fb3380fe2b2d633c895d1430c84"/>

九、床单便清洗干净了。

/iknow-pic.cdn.bcebos.com/78310a55b319ebc4fa53e3bc8d26cffc1e1716ef"target="_blank"title="点击查看大图"class="ikqb_img_alink">/iknow-pic.cdn.bcebos.com/78310a55b319ebc4fa53e3bc8d26cffc1e1716ef?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto"esrc="https://iknow-pic.cdn.bcebos.com/78310a55b319ebc4fa53e3bc8d26cffc1e1716ef"/>

---