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htmlvb.netstringbuilder

vb.net Stringbuilder to create HTML file

I am using a StringBuilder to create a HTML file from my DataTable. The file is created but when I open it in the webbrowser I have to scroll all the way down to see the table. In other words there is a big blank page first with nothing at all.

Public Function ConvertToHtmlFile(ByVal myTable As DataTable) As String
        Dim myBuilder As New StringBuilder
        If myTable Is Nothing Then
            Throw New System.ArgumentNullException("myTable")
        Else
                
            'Open tags and write the top portion. 
            myBuilder.Append("<html xmlns='http://www.w3.org/1999/xhtml'>")
            myBuilder.Append("<head>")
            myBuilder.Append("<title>")
            myBuilder.Append("Page-")
            myBuilder.Append("CLAS Archive")
            myBuilder.Append("</title>")
            myBuilder.Append("</head>")
            myBuilder.Append("<body>")
            myBuilder.Append("<br /><table border='1px' cellpadding='5' cellspacing='0' ")
            myBuilder.Append("style='border: solid 1px Silver; font-size: x-small;'>")


            myBuilder.Append("<br /><tr align='left' valign='top'>")

            For Each myColumn As DataColumn In myTable.Columns
                myBuilder.Append("<br /><td align='left' valign='top' style='border: solid 1px blue;'>")
                myBuilder.Append(myColumn.ColumnName)
                myBuilder.Append("</td><p>")
            Next

            myBuilder.Append("</tr><p>")

            'Add the data rows.
            For Each myRow As DataRow In myTable.Rows
                myBuilder.Append("<br /><tr align='left' valign='top'>")
                For Each myColumn As DataColumn In myTable.Columns
                    myBuilder.Append("<br /><td align='left' valign='top' style='border: solid 1px blue;'>")
                    myBuilder.Append(myRow(myColumn.ColumnName).ToString())
                    myBuilder.Append("</td><p>")
                Next
            Next
            myBuilder.Append("</tr><p>")
        End If

        'Close tags. 
        myBuilder.Append("</table><p>")
        myBuilder.Append("</body>")
        myBuilder.Append("</html>")

        'Get the string for return. myHtmlFile = myBuilder.ToString();
        Dim myHtmlFile As String = myBuilder.ToString()

        Return myHtmlFile
    End Function
Solution

  • A sample HTML table (from the MDN docs):

    <table>
    <thead>
        <tr>
            <th colspan="2">The table header</th>
        </tr>
    </thead>
    <tbody>
        <tr>
            <td>The table body</td>
            <td>with two columns</td>
        </tr>
    </tbody>
</table>

    If you study the "permitted content" within the various table elements (also dive deeper, for instance <tr>), there cannot be a <br> or <p> between <table>, <tr> or <td> elements, only table-related elements are allowed.

    A <tr> is already a row in the table, so you don't need breaks or paragraphs to move it to a separate row.