尝试将 <hr> 标记放入 stringBuilderObject.Append() VB.net 时出现对象引用错误

Object Reference Error while trying to put <hr> tag in stringBuilderObject.Append() VB.net

我的主要目的是使用 VB.net 为 pdf 中的一些单词添加蓝色下划线。代码如下:

strSignHTML.Append("<TD class=""TBLDATA"" width=""25%"" align=left><br /><br>")
strSignHTML.Append("<hr color=""midnightblue"">")
strSignHTML.Append("</TD>")
strSignHTML.Append("<td width=50%>&nbsp;</td>")
strSignHTML.Append("<td class=""TBLDATA"" width=""25%"" align=left> <br>")
strSignHTML.Append("<hr color=""midnightblue"">")
strSignHTML.Append("</td>")
strSignHTML.Append("</tr>")
strSignHTML.Append("<tr>")
strSignHTML.Append("<td class=""TBLDATA"">")
strSignHTML.Append("<font color=""midnightblue""><b>Signature</b></font>")
strSignHTML.Append("</td>")
strSignHTML.Append("<td width=50%>&nbsp;</td>")
strSignHTML.Append("<td class=""TBLDATA"">")
strSignHTML.Append("<font color=""midnightblue""><b>Date</b></font>")
strSignHTML.Append("</td>")
strSignHTML.Append("</tr>")
strSignHTML.Append("<tr>")

导入库后

Imports System.Text

并实际将 strSignHTML 设置为 StringBuilder 你可以开始了

    Dim strSignHTML As New StringBuilder
    strSignHTML.Append("<TD class=""TBLDATA"" width=""25%"" align=left><br /><br>")
    strSignHTML.Append("<hr color=""midnightblue"">")
    strSignHTML.Append("</TD>")
    strSignHTML.Append("<td width=50%>&nbsp;</td>")
    strSignHTML.Append("<td class=""TBLDATA"" width=""25%"" align=left> <br>")
    strSignHTML.Append("<hr color=""midnightblue"">")
    strSignHTML.Append("</td>")
    strSignHTML.Append("</tr>")
    strSignHTML.Append("<tr>")
    strSignHTML.Append("<td class=""TBLDATA"">")
    strSignHTML.Append("<font color=""midnightblue""><b>Signature</b></font>")
    strSignHTML.Append("</td>")
    strSignHTML.Append("<td width=50%>&nbsp;</td>")
    strSignHTML.Append("<td class=""TBLDATA"">")
    strSignHTML.Append("<font color=""midnightblue""><b>Date</b></font>")
    strSignHTML.Append("</td>")
    strSignHTML.Append("</tr>")
    strSignHTML.Append("<tr>")

    Dim myString As String = strSignHTML.ToString

即便如此我还是宁愿使用CDATA

Dim myString As String = <![CDATA[
                <TD class="TBLDATA" width="25%" align=left><br /><br>
                <hr color="midnightblue">
                </TD>
                <td width=50%>&nbsp;</td>
                <td class="TBLDATA" width="25%" align=left> <br>
                <hr color="midnightblue">
                </td>
                </tr>
                <tr>
                <td class="TBLDATA">
                <font color = "midnightblue"><b>Signature</b></font>
                </td>
                <td width = 50% >& nbsp;</td>
                <td class="TBLDATA">
                <font color = "midnightblue"><b>Date</b></font>
                </td>
                </tr>
                <tr>]]>.Value