Modifying .resx file in C#

Solution 1:

There's a whole namespace for resource management: System.Resources. Check out the ResourceManager class, as well as ResXResourceReader and ResXResourceWriter.

http://msdn.microsoft.com/en-us/library/system.resources.aspx

I managed to lay my hands on a very old debug method that I used to use at one point when I was testing some resource related stuff. This should do the trick for you.

public static void UpdateResourceFile(Hashtable data, String path)
    {
        Hashtable resourceEntries = new Hashtable();

        //Get existing resources
        ResXResourceReader reader = new ResXResourceReader(path);
        if (reader != null)
        {
            IDictionaryEnumerator id = reader.GetEnumerator();
            foreach (DictionaryEntry d in reader)
            {
                if (d.Value == null)
                    resourceEntries.Add(d.Key.ToString(), "");
                else
                    resourceEntries.Add(d.Key.ToString(), d.Value.ToString());
            }
            reader.Close();
        }

        //Modify resources here...
        foreach (String key in data.Keys)
        {
            if (!resourceEntries.ContainsKey(key))
            {

                String value = data[key].ToString();
                if (value == null) value = "";

                resourceEntries.Add(key, value);
            }
        }

        //Write the combined resource file
            ResXResourceWriter resourceWriter = new ResXResourceWriter(path);

            foreach (String key in resourceEntries.Keys)
            {
                resourceWriter.AddResource(key, resourceEntries[key]);
            }
            resourceWriter.Generate();
            resourceWriter.Close();

    }

Solution 2:

    public static void AddOrUpdateResource(string key, string value)
    {
        var resx = new List<DictionaryEntry>();
        using (var reader = new ResXResourceReader(resourceFilepath))
        {
            resx = reader.Cast<DictionaryEntry>().ToList();
            var existingResource = resx.Where(r => r.Key.ToString() == key).FirstOrDefault();
            if (existingResource.Key == null && existingResource.Value == null) // NEW!
            {
                resx.Add(new DictionaryEntry() { Key = key, Value = value });
            }
            else // MODIFIED RESOURCE!
            {
                var modifiedResx = new DictionaryEntry() 
                    { Key = existingResource.Key, Value = value };
                resx.Remove(existingResource);  // REMOVING RESOURCE!
                resx.Add(modifiedResx);  // AND THEN ADDING RESOURCE!
            }
        }
        using (var writer = new ResXResourceWriter(ResxPathEn))
        {
            resx.ForEach(r =>
                        {
                            // Again Adding all resource to generate with final items
                            writer.AddResource(r.Key.ToString(), r.Value.ToString());
                        });
            writer.Generate();
        }
    }

Solution 3:

If you want to keep the existing comments in the resource files then use this (Based on SirMoreno's code modified)

 public static void UpdateResourceFile(Hashtable data, String path)
    {
        Hashtable resourceEntries = new Hashtable();

        //Get existing resources
        ResXResourceReader reader = new ResXResourceReader(path);
        reader.UseResXDataNodes = true;
        ResXResourceWriter resourceWriter = new ResXResourceWriter(path);
        System.ComponentModel.Design.ITypeResolutionService typeres = null;
        if (reader != null)
        {
            IDictionaryEnumerator id = reader.GetEnumerator();
            foreach (DictionaryEntry d in reader)
            {
                //Read from file:
                string val = "";
                if (d.Value == null)
                    resourceEntries.Add(d.Key.ToString(), "");
                else
                {
                    val = ((ResXDataNode)d.Value).GetValue(typeres).ToString();
                    resourceEntries.Add(d.Key.ToString(), val);

                }

                //Write (with read to keep xml file order)
                ResXDataNode dataNode = (ResXDataNode)d.Value;

                //resourceWriter.AddResource(d.Key.ToString(), val);
                resourceWriter.AddResource(dataNode);

            }
            reader.Close();
        }

        //Add new data (at the end of the file):
        Hashtable newRes = new Hashtable();
        foreach (String key in data.Keys)
        {
            if (!resourceEntries.ContainsKey(key))
            {

                String value = data[key].ToString();
                if (value == null) value = "";

                resourceWriter.AddResource(key, value);
            }
        }

        //Write to file
        resourceWriter.Generate();
        resourceWriter.Close();

    }

Solution 4:

Womp got it right (10x).

But here is a code that keeps the XML file order, add new at the end of the file. (for source control)

    //Need dll System.Windows.Forms
    public static void UpdateResourceFile(Hashtable data, String path)
    {
        Hashtable resourceEntries = new Hashtable();

        //Get existing resources
        ResXResourceReader reader = new ResXResourceReader(path);
        ResXResourceWriter resourceWriter = new ResXResourceWriter(path);

        if (reader != null)
        {
            IDictionaryEnumerator id = reader.GetEnumerator();
            foreach (DictionaryEntry d in reader)
            {
                //Read from file:
                string val = "";
                if (d.Value == null)
                    resourceEntries.Add(d.Key.ToString(), "");
                else
                {
                    resourceEntries.Add(d.Key.ToString(), d.Value.ToString());
                    val = d.Value.ToString();
                }

                //Write (with read to keep xml file order)
                resourceWriter.AddResource(d.Key.ToString(), val);

            }
            reader.Close();
        }

        //Add new data (at the end of the file):
        Hashtable newRes = new Hashtable();
        foreach (String key in data.Keys)
        {
            if (!resourceEntries.ContainsKey(key))
            {

                String value = data[key].ToString();
                if (value == null) value = "";

                resourceWriter.AddResource(key, value);
            }
        }

        //Write to file
        resourceWriter.Generate();
        resourceWriter.Close();

    }