HTML中的边框底部未显示

我正在尝试在VB.Net上用HTML设计一封电子邮件，但是边框底部没有显示，我也没有看到代码有任何错误

您可以在此处看到，边框底部未显示：

预期的边框底部应如下所示，底部有一条小灰线：

下面是我的底部边框代码：

                    mm.Body = mm.Body & "<tbody><tr>"
                    mm.Body = mm.Body & "<td style=min-height:65px;background-color:#000000;border-bottom:1px solid #4d4b48;>"
                    mm.Body = mm.Body & "<img src=https://image.ibb.co/gf2547/Email_Header_PNG.png width=538 height=65 alt=Steam>"
                    mm.Body = mm.Body & "</td>"
                    mm.Body = mm.Body & "</tr>"

mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“

您可以在此处查看整个电子邮件的整个HTML代码：

                    mm.Body = mm.Body & "<div>"
                    mm.Body = mm.Body & "<table style=width:538px;background-color:#393836; align=center cellspacing=0 cellpadding=0>"


                    mm.Body = mm.Body & "<tbody><tr>"
                    mm.Body = mm.Body & "<td style=min-height:65px;background-color:#000000;border-bottom:1px solid #4d4b48;>"
                    mm.Body = mm.Body & "<img src=https://image.ibb.co/gf2547/Email_Header_PNG.png width=538 height=65 alt=Steam>"
                    mm.Body = mm.Body & "</td>"
                    mm.Body = mm.Body & "</tr>"


                    mm.Body = mm.Body & "<tr>"
                    mm.Body = mm.Body & "<td bgcolor=#370E0E>"
                    mm.Body = mm.Body & "<table width=470 border=0 align=center cellpadding=0 cellspacing=0 style=padding-left:5px;padding-right:5px;padding-bottom:10px;>"
                    mm.Body = mm.Body & "<tbody><tr bgcolor=#370E0E>"
                    mm.Body = mm.Body & "<td style=padding-top:32px;>"
                    mm.Body = mm.Body & "<font color=#F12121> <h1> Dear " + firstname + " " + lastname + ", </h1> </font>"
                    mm.Body = mm.Body & "</td>"
                    mm.Body = mm.Body & "</tr>"
                    mm.Body = mm.Body & "<tr>"
                    mm.Body = mm.Body & "<td style=padding-top:12px;>"
                    mm.Body = mm.Body & "<font color=#c6d4df> <h3> The Newly Generated Password you need to login into your account is : </h3> </font>"
                    mm.Body = mm.Body & "</td>"
                    mm.Body = mm.Body & "</tr>"
                    mm.Body = mm.Body & "<tr>"
                    mm.Body = mm.Body & "<td>"
                    mm.Body = mm.Body & "<div>"
                    mm.Body = mm.Body & "<font color=#F12121> <h1> " + lbl1.Text + " </h1> </font>"
                    mm.Body = mm.Body & "</div>"
                    mm.Body = mm.Body & "</td>"
                    mm.Body = mm.Body & "</tr>"
                    mm.Body = mm.Body & "<tr bgcolor=#2A0808>"
                    mm.Body = mm.Body & "<td style=padding:20px;font-size:12px;line-height:17px;color:#c6d4df; font-family:Arial, Helvetica, sans-serif;>"
                    mm.Body = mm.Body & "<p style=padding-bottom:10px;color:#c6d4df;>This Email and Password was generated upon your request. The Verification Attempt included your correct Umbrella ID and Email.</p>"
                    mm.Body = mm.Body & "<p style=padding-bottom:10px;color:#c6d4df;>The Generated Password is required to complete the login.  <span style=color:#ffffff;font-weight:bold;>No one can access your account without also accessing this email.</span></p>"
                    mm.Body = mm.Body & "<p style=padding-bottom:10px;color:#c6d4df;><span style=color:#ffffff;font-weight:bold;>If you are not attempting to login</span> then please change your Umbrella Account password and consider changing your email password as well to ensure your account security.</p>"
                    mm.Body = mm.Body & "<p style=padding-top:10px;color:#61696d;>If you are unable to access your account then you may choose to <a rel=nofollow style=color:#8f98a0; target=_blank href=https://help.steampowered.com/#HelpUnauthorizedLogin?stoken=PbSXLaCZRzquMH0O2wIxCSPQlkzzZ%2BYDb0OWGxQEIhILTU1sRh69ojyLplpI6nFD8cPAAi0E59y0hViMAOj9ekVlQX0ekbDB0fKFEYzrO1M%3D> lock your account.</"
                    mm.Body = mm.Body & "a> Once locked you must request <a rel=nofollow style=color:#8f98a0; target=_blank href=https://support.steampowered.com/newticket.php?category=11> Umbrella Support's Assistance </"
                    mm.Body = mm.Body & "a> in recovering and unlocking it.  Until the account is unlocked you will be restricted from accessing any of the Umbrella Corporation's Property and will be held in Solitary Confinement.</p>"
                    mm.Body = mm.Body & "</td>"
                    mm.Body = mm.Body & "</tr>"
                    mm.Body = mm.Body & "<tr>"
                    mm.Body = mm.Body & "<td style=font-size:12px;color:#6d7880;padding-top:16px;padding-bottom:60px;>"
                    mm.Body = mm.Body & "Umbrella Corporation Personnel Security Observation Team<br>"
                    mm.Body = mm.Body & "<a rel=nofollow style=color:#8f98a0; target=_blank href=https://help.steampowered.com/>https://support.umbrellacorp.uc </a><br>"
                    mm.Body = mm.Body & "</td>"
                    mm.Body = mm.Body & "</tr>"
                    mm.Body = mm.Body & "</tbody></table>"
                    mm.Body = mm.Body & "</td>"
                    mm.Body = mm.Body & "</tr>"
                    mm.Body = mm.Body & "<tr style=background-color:#000000;>"
                    mm.Body = mm.Body & "<td style=padding:12px 24px;>"
                    mm.Body = mm.Body & "<table cellpadding=0 cellspacing=0>"
                    mm.Body = mm.Body & "<tbody><tr>"
                    mm.Body = mm.Body & "<td width=92>"
                    mm.Body = mm.Body & "<img src=https://image.ibb.co/krMnHS/Email_Footer_2_PNG.png width=92 height=26 alt=Valve®>"
                    mm.Body = mm.Body & "</td>"
                    mm.Body = mm.Body & "<td style=font-size:11px;color:#595959;padding-left:12px;>Umbrella Corporation. PO Box 1688 Bellevue, WA 98009.<br> "
                    mm.Body = mm.Body & "All rights reserved. All trademarks are property of their respective owners in the US and other countries. <br>"
                    mm.Body = mm.Body & "</td>"
                    mm.Body = mm.Body & "</tr>"
                    mm.Body = mm.Body & "</tbody></table>"
                    mm.Body = mm.Body & "</td>"
                    mm.Body = mm.Body & "</tr>"
                    mm.Body = mm.Body & "</tbody></table>"
                    mm.Body = mm.Body & "</div>"

mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“亲爱的”+firstname+“+lastname+”，“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“您需要登录帐户的新生成密码是：”
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“”+lbl1.Text+“”
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
此电子邮件和密码是根据您的请求生成的。验证尝试包括正确的伞ID和电子邮件。
”
mm.Body=mm.Body&“
完成登录需要生成的密码。没有人可以访问您的帐户而不访问此电子邮件。
”
My.My= mm .Mype和“
如果您没有尝试登录，请更改您的伞帐户密码，并考虑更改您的电子邮件密码，以确保您的帐户安全性。
mm.Body=mm.Body&“
如果您无法访问您的帐户，则可以选择
”
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“美国华盛顿州贝尔维尤1688号邮政信箱，邮编：98009.
”
mm.Body=mm.Body&“保留所有权利。所有商标均为其各自所有者在美国和其他国家/地区的财产。
”
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“
mm.Body=mm.Body&“

您的单元格高度比图像+边框短。在

td

上尝试67px的最小高度，或将img高度设为63像素（至少要测试）

---

如果不起作用，请尝试在

td

上填充1px，您确定

标记位于

标记内吗

    <table>
      <tr>
        <td >
          <img src=https://image.ibb.co/gf2547/Email_Header_PNG.png width=538 height=65 alt=Steam>
        </td>
      </tr>
    </table>

---

您需要在标记中的属性值周围加上引号，例如：

mm.Body = mm.Body & "<td style=""min-height:65px;background-color:#000000;border-bottom:1px solid #4d4b48;"">"

mm.Body=mm.Body&“

对代码中的所有其他属性重复该操作，

style

或其他

如果没有引号，您的HTML标记就无效，并且在看到第一个无效的属性值字符（在本例中可能是

-

或

：

）后，解析HTML标记的内容最多也会放弃，从而导致整个

样式

属性基本上被忽略

鉴于电子邮件HTML已经非常挑剔，您应该确保您的标记尽可能有效

---

最后，为了可维护性，我建议以某种方式使用可替换标记或其他东西存储HTML，并在VB.NET代码中替换它们。逐行将标记拼接在一起无助于发现标记中的错误，例如缺少结束标记。它还防止您在不必重新编译代码的情况下更改布局。

是否尝试在标记中添加引号？如果正确引用属性值，会有什么区别？（例如，

mm.Body=mm.Body&

@Cᴏ你不能在VB.Net中的HTML代码上加引号，因为它们会将其作为一个整体来阅读line@LuciferRodstark：您当然可以，也应该这样做。注意我是如何通过将两个相邻放置来转义它们的？编译该代码时，它将被解释为一个引号。@Cᴏ哦，我明白了，我也试过使用你的代码，但边框底部会弹出？我不知道为什么？我们的代码是一样的，虽然只是引用而已。我试过了所有代码，但都是一样的