Populating Resource.resx file from database

Question

I'm trying to populate my resource file at startup from my database. Everytime a page loads it should check for the active language. I'm currently stuck at the problem of how to insert in a resource file. I tried the obvious way but it didn't work.

 ResourceFile = TempTransMessage;

Any idea how to do this?

Answer 1

You can generate resx files from data stored in a database using Microsoft's Text Template Transformation Toolkit (usually referred to as "T4"). Scott Hanselman has published a blog post on the subject which will give you a good idea of how this works.

An example of a .tt file that would do just that:

<#@ template debug="false" hostspecific="false" language="C#" #>
<#@ assembly name="System.Core" #>
<#@ assembly name="System.Data" #>
<#@ assembly name="System.Configuration" #>
<#@ assembly name="System.Web" #>
<#@ import namespace="System.Text" #>
<#@ import namespace="System.Collections.Generic" #>
<#@ import namespace="System.Data" #>
<#@ import namespace="System.Data.SqlClient" #>
<#@ import namespace="System.Web.Configuration" #>
<#@ import namespace="System.Web" #>
<#@ output extension=".resx" #>
<#
    SqlConnection _Connection;
    SqlCommand _Command;

    _Connection = new SqlConnection();

    /// Open the connection to the database
    _Connection.ConnectionString = "Initial Catalog=YourCatalog;Integrated Security=true;Data Source=YourDatasource";

    // Open the connection
    _Connection.Open();

    _Command = _Connection.CreateCommand();
    _Command.CommandType = CommandType.Text;
    _Command.CommandText = "select Id,Value from MyTable";

    SqlDataReader reader = _Command.ExecuteReader();

#>
<?xml version="1.0" encoding="utf-8"?>
<root>
  <!-- 
    Microsoft ResX Schema 

    Version 2.0

    The primary goals of this format is to allow a simple XML format 
    that is mostly human readable. The generation and parsing of the 
    various data types are done through the TypeConverter classes 
    associated with the data types.

    Example:

    ... ado.net/XML headers & schema ...
    <resheader name="resmimetype">text/microsoft-resx</resheader>
    <resheader name="version">2.0</resheader>
    <resheader name="reader">System.Resources.ResXResourceReader, System.Windows.Forms, ...</resheader>
    <resheader name="writer">System.Resources.ResXResourceWriter, System.Windows.Forms, ...</resheader>
    <data name="Name1"><value>this is my long string</value><comment>this is a comment</comment></data>
    <data name="Color1" type="System.Drawing.Color, System.Drawing">Blue</data>
    <data name="Bitmap1" mimetype="application/x-microsoft.net.object.binary.base64">
        <value>[base64 mime encoded serialized .NET Framework object]</value>
    </data>
    <data name="Icon1" type="System.Drawing.Icon, System.Drawing" mimetype="application/x-microsoft.net.object.bytearray.base64">
        <value>[base64 mime encoded string representing a byte array form of the .NET Framework object]</value>
        <comment>This is a comment</comment>
    </data>

    There are any number of "resheader" rows that contain simple 
    name/value pairs.

    Each data row contains a name, and value. The row also contains a 
    type or mimetype. Type corresponds to a .NET class that support 
    text/value conversion through the TypeConverter architecture. 
    Classes that don't support this are serialized and stored with the 
    mimetype set.

    The mimetype is used for serialized objects, and tells the 
    ResXResourceReader how to depersist the object. This is currently not 
    extensible. For a given mimetype the value must be set accordingly:

    Note - application/x-microsoft.net.object.binary.base64 is the format 
    that the ResXResourceWriter will generate, however the reader can 
    read any of the formats listed below.

    mimetype: application/x-microsoft.net.object.binary.base64
    value   : The object must be serialized with 
            : System.Runtime.Serialization.Formatters.Binary.BinaryFormatter
            : and then encoded with base64 encoding.

    mimetype: application/x-microsoft.net.object.soap.base64
    value   : The object must be serialized with 
            : System.Runtime.Serialization.Formatters.Soap.SoapFormatter
            : and then encoded with base64 encoding.

    mimetype: application/x-microsoft.net.object.bytearray.base64
    value   : The object must be serialized into a byte array 
            : using a System.ComponentModel.TypeConverter
            : and then encoded with base64 encoding.
    -->
  <xsd:schema id="root" xmlns="" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:msdata="urn:schemas-microsoft-com:xml-msdata">
    <xsd:import namespace="http://www.w3.org/XML/1998/namespace" />
    <xsd:element name="root" msdata:IsDataSet="true">
      <xsd:complexType>
        <xsd:choice maxOccurs="unbounded">
          <xsd:element name="metadata">
            <xsd:complexType>
              <xsd:sequence>
                <xsd:element name="value" type="xsd:string" minOccurs="0" />
              </xsd:sequence>
              <xsd:attribute name="name" use="required" type="xsd:string" />
              <xsd:attribute name="type" type="xsd:string" />
              <xsd:attribute name="mimetype" type="xsd:string" />
              <xsd:attribute ref="xml:space" />
            </xsd:complexType>
          </xsd:element>
          <xsd:element name="assembly">
            <xsd:complexType>
              <xsd:attribute name="alias" type="xsd:string" />
              <xsd:attribute name="name" type="xsd:string" />
            </xsd:complexType>
          </xsd:element>
          <xsd:element name="data">
            <xsd:complexType>
              <xsd:sequence>
                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
                <xsd:element name="comment" type="xsd:string" minOccurs="0" msdata:Ordinal="2" />
              </xsd:sequence>
              <xsd:attribute name="name" type="xsd:string" use="required" msdata:Ordinal="1" />
              <xsd:attribute name="type" type="xsd:string" msdata:Ordinal="3" />
              <xsd:attribute name="mimetype" type="xsd:string" msdata:Ordinal="4" />
              <xsd:attribute ref="xml:space" />
            </xsd:complexType>
          </xsd:element>
          <xsd:element name="resheader">
            <xsd:complexType>
              <xsd:sequence>
                <xsd:element name="value" type="xsd:string" minOccurs="0" msdata:Ordinal="1" />
              </xsd:sequence>
              <xsd:attribute name="name" type="xsd:string" use="required" />
            </xsd:complexType>
          </xsd:element>
        </xsd:choice>
      </xsd:complexType>
    </xsd:element>
  </xsd:schema>
  <resheader name="resmimetype">
    <value>text/microsoft-resx</value>
  </resheader>
  <resheader name="version">
    <value>2.0</value>
  </resheader>
  <resheader name="reader">
    <value>System.Resources.ResXResourceReader, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
  </resheader>
  <resheader name="writer">
    <value>System.Resources.ResXResourceWriter, System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089</value>
  </resheader>
  <#        
while(reader.Read())
{#>
  <data name="<#= reader["Id"]#>" xml:space="preserve">
    <value><#= HttpUtility.HtmlEncode(reader["Value"].ToString()) #></value>
  </data>
<#
}
#>
</root>
<#
    reader.Close();
    reader.Dispose();

    /// Close the SqlDataReader if exist and close the connection to the database
   _Connection.Close();
   _Connection.Dispose();
#>

Answer 2

Unless you need to redistribute those resource files (in which case Diego's answer is a very good option), you may also want to check out how to retrieve your resources directly from the DB. Resource management uses providers, you can have a custom provider check out databases directly.

In fact, Rick Strahl's globalization package does that already if that's what you need