update connectionstring in app.config file at run time in C#

Question

I have created an application and in that application am going to insert, update and delete data operation in database

I have also created a form for connection settings, where user can update server name, datatbase and user id and password. I have stored my connection string in app.config file.

My problem is, how can I update connection string in app.config file at run time?

Possible duplicate: https://stackoverflow.com/q/502411/1518546 — John Cummings, Nov 28 '17 at 14:27

score 2 · Answer 1 · edited Jul 25 '12 at 12:15

2

You can try this:

Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
config.ConnectionStrings.ConnectionStrings.Add(new ConnectionStringSettings("MyConnectionString",String.Format("DataSource={0};InitialCatalog={1};IntegratedSecurity={2}","testing", "testing2", "Testing6")));
config.Save(ConfigurationSaveMode.Modified, true);
ConfigurationManager.RefreshSection("connectionStrings");

edited Jul 25 '12 at 12:15

Mennan

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answered Jul 25 '12 at 07:43

Rohit Vyas

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1

Note that this will edit the config file in the bin folder - if you are using for multiple tries, you may need to use another method – Ruskin Dec 17 '14 at 09:59
1

Thanks @Ruskin I was wondering why my config wasn't updating :) – hatsrumandcode Mar 02 '19 at 15:32

score 0 · Answer 2 · answered Jul 25 '12 at 07:37

0

You can try this:

private void changeValue(String KeyName, String KeyValue)
{
System.Configuration.Configuration config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);

// Update the setting.
config.AppSettings.Settings[KeyName].Value = KeyValue;

// Save the configuration file.
config.Save(ConfigurationSaveMode.Modified);

// Force a reload of the changed section.
ConfigurationManager.RefreshSection("appSettings");
}

answered Jul 25 '12 at 07:37

Mennan

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Thank you for your reply,but i am not understood where it should write in my application .i add this code in button_click event but giving me error.error is **The name 'ConfigurationUserLevel' does not exist in the current context** and many others – user1482953 Jul 25 '12 at 11:45
Did you add ConfigurationManager dll to your project ? – Mennan Jul 25 '12 at 12:08
thank you sir ,my connectiostring is updating ,but after closing application,and open again ,i see my connectiostring it remains same as before updating. – user1482953 Jul 26 '12 at 12:59
This example is for entries and not for the per the post. – Galactic Dec 13 '21 at 20:52

score 0 · Answer 3 · answered Jan 02 '13 at 17:06

0

I believe that your App.Config is not updating because it is using the vshost. I had this issue today, and I tried the solutions of this post, but running on VisualStudio, so the file was the same. Outside VS it worked as a charm.

answered Jan 02 '13 at 17:06

rodrigocl

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score 0 · Answer 4 · answered Jul 18 '13 at 14:24

App.cofig Code

      <?xml version="1.0" encoding="utf-8"?>
        <configuration>
     <configSections>
            <section name="dataConfiguration"type="Microsoft.Practices.EnterpriseLibrary.Data.Configuration.DatabaseSettings, Microsoft.Practices.EnterpriseLibrary.Data, Version=3.1.0.0, Culture=neutral,        PublicKeyToken=b03f5f7f11d50a3a" />
     </configSections>
    <connectionStrings>
  <add name="DbDatabase" providerName="System.Data.SqlClient" connectionString=""/>
</connectionStrings>

C# Code

   public void updateConfigFile(string con)
    {
        //updating config file
        XmlDocument XmlDoc = new XmlDocument();
        //Loading the Config file
        XmlDoc.Load(AppDomain.CurrentDomain.SetupInformation.ConfigurationFile);
       // XmlDoc.Load("App.config");
        foreach (XmlElement xElement in XmlDoc.DocumentElement)
        {
            if (xElement.Name == "connectionStrings")
            {
                //setting the coonection string
                xElement.FirstChild.Attributes[2].Value = con;
            }
        }
        //writing the connection string in config file
        XmlDoc.Save(AppDomain.CurrentDomain.SetupInformation.ConfigurationFile);
        //XmlDoc.Save("App.config");
    }



 private void btn_Connect_Click(object sender, EventArgs e)
    {
        StringBuilder Con = new StringBuilder("Data Source=");
        Con.Append(txt_ServerName.Text);
        Con.Append(";Initial Catalog=");
        Con.Append(txt_DatabaseName.Text);
        if (String.IsNullOrEmpty(txt_UserId.Text) &&String.IsNullOrEmpty(txt_Password.Text))
            Con.Append(";Integrated Security=true;");
        else
        {
            Con.Append(";User Id=");
            Con.Append(txt_UserId.Text);
            Con.Append(";Password=");
            Con.Append(txt_Password.Text);
        }
        string strCon = Con.ToString();
        updateConfigFile(strCon);

        DatabaseTableDA da = new DatabaseTableDA();
        tableList = da.Select_Tables();
        this.lstTables.DataSource = tableList;
    }

score 0 · Answer 5 · edited Aug 26 '16 at 08:50

0

 var config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
 var connectionStringsSection = (ConnectionStringsSection)config.GetSection("connectionStrings");
 connectionStringsSection.ConnectionStrings["ClientCN"].ConnectionString = "server=localhost;user=root;port=3306;password=abc";
 config.Save();
  ConfigurationManager.RefreshSection("connectionStrings");

edited Aug 26 '16 at 08:50

tenten

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answered Aug 26 '16 at 08:18

sarvjeet

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score 0 · Answer 6 · edited Sep 06 '16 at 18:24

try this:

var config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
var connectionStringsSection = (ConnectionStringsSection)config.GetSection("connectionStrings");
connectionStringsSection.ConnectionStrings["ClientCN"].ConnectionString = "server=localhost;user=root;port=3306;password=abc";
config.Save();
ConfigurationManager.RefreshSection("connectionStrings");

update connectionstring in app.config file at run time in C#

6 Answers6