Save and use CSS from database in ASP.Net using C# and VB.Net

Hi ilanocf

In the PageLoad event you need to retrieve the css from database and write to the Header of the page using the style tag.

Please refer below sample.

I have refered below article for inserting data in database.

Save (Insert) and Retrieve (Display) TinyMCE contents from database in ASP.Net

HTML

<asp:TextBox ID="txtHTMLContent" runat="server" TextMode="MultiLine" />
<br />
<asp:Button ID="btnSubmit" Text="Submit" runat="server" OnClick="Submit" />
<hr />
<table>
    <tr>
        <th>Customer Id</th>
        <th>Name</th>
        <th>Country</th>
    </tr>
    <tr>
        <td>1</td>
        <td>John Hammond</td>
        <td>United States</td>
    </tr>
    <tr>
        <td>2</td>
        <td>Mudassar Khan</td>
        <td>India</td>
    </tr>
    <tr>
        <td>3</td>
        <td>Suzanne Mathews</td>
        <td> France </td>
    </tr>
    <tr>
        <td>4</td>
        <td>Robert Schidner</td>
        <td>Russia</td>
    </tr>
</table>
<br />
<div class="container">
    <div class="row">
        <div class="col-md-4">
            <img src="https://www.aspsnippets.com/images/Logo_new.png" style="background-color: #0090CB;" /></div>
        <div class="col-md-8">
            Welcome to ASPSnippets.</div>
    </div>
</div>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.2/css/bootstrap.min.css" />
<script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/tinymce/4.0.20/tinymce.min.js"></script>
<script type="text/javascript">
    tinymce.init({ selector: 'textarea', width: 500 });
</script>

Namespaces

C#

using System.Data;
using System.Data.SqlClient;
using System.Configuration;

VB.Net

Imports System.Data
Imports System.Data.SqlClient
Imports System.Configuration

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        AddCSS();
    }
}

private void AddCSS()
{
    string css = string.Empty;
    string conString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(conString))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT [Content] FROM [HTMLContent]", con))
        {
            con.Open();
            css = Convert.ToString(cmd.ExecuteScalar());
            con.Close();
        }
    }

    HtmlGenericControl style = new HtmlGenericControl();
    style.TagName = "style";
    style.Attributes.Add("type", "text/css");
    style.InnerHtml = css;
    this.Page.Header.Controls.Add(style);
}

protected void Submit(object sender, EventArgs e)
{
    string conString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
    using (SqlConnection con = new SqlConnection(conString))
    {
        using (SqlCommand cmd = new SqlCommand("INSERT INTO [HTMLContent] VALUES (@Content)", con))
        {
            cmd.Parameters.AddWithValue("@Content", txtHTMLContent.Text.Replace("<p>", string.Empty).Replace("</p>", string.Empty).Replace("&nbsp;", string.Empty));
            con.Open();
            cmd.ExecuteNonQuery();
            con.Close();
        }
    }

    Response.Redirect(Request.Url.AbsoluteUri);
}

VB.Net

Protected Sub Page_Load(sender As Object, e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        AddCSS()
    End If
End Sub

Private Sub AddCSS()
    Dim css As String = String.Empty
    Dim conString As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As SqlConnection = New SqlConnection(conString)
        Using cmd As SqlCommand = New SqlCommand("SELECT [Content] FROM [HTMLContent]", con)
            con.Open()
            css = Convert.ToString(cmd.ExecuteScalar())
            con.Close()
        End Using
    End Using

    Dim style As HtmlGenericControl = New HtmlGenericControl()
    style.TagName = "style"
    style.Attributes.Add("type", "text/css")
    style.InnerHtml = css
    Me.Page.Header.Controls.Add(style)
End Sub

Protected Sub Submit(ByVal sender As Object, ByVal e As EventArgs)
    Dim conString As String = ConfigurationManager.ConnectionStrings("constr").ConnectionString
    Using con As SqlConnection = New SqlConnection(conString)
        Using cmd As SqlCommand = New SqlCommand("INSERT INTO [HTMLContent] VALUES (@Content)", con)
            cmd.Parameters.AddWithValue("@Content", txtHTMLContent.Text.Replace("<p>", String.Empty).Replace("</p>", String.Empty).Replace("&nbsp;", String.Empty))
            con.Open()
            cmd.ExecuteNonQuery()
            con.Close()
        End Using
    End Using

    Response.Redirect(Request.Url.AbsoluteUri)
End Sub

Screenshot

Web Page with applied CSS from database

Inserted CSS in database