# SetBaseReferenceForConfig(string, string)

> Sets the base configuration reference for the specified build configuration.

## Definition

* **Type:** Method
* **Namespace:** [UnityEditor.iOS.Xcode](/engine/6000.3/script-reference/unityeditor/ios/xcode.md)
* **Assembly:** UnityEditor.iOS.Extensions.Xcode

```csharp
public void SetBaseReferenceForConfig(string configGuid, string baseReference)
```

### Parameters

**** (\[string]\(https\://learn.microsoft.com/dotnet/api/system.string)): The GUID of the build configuration as returned by [PBXProject.BuildConfigByName](/engine/6000.3/script-reference/unityeditor/ios/xcode/pbxproject/buildconfigbyname.md).**** (\[string]\(https\://learn.microsoft.com/dotnet/api/system.string)): The GUID of the configuration file to be used as the base reference.

### Remarks

**Note**: If the baseReference parameter is null, the base reference is removed.

### Examples

```csharp
using UnityEngine;
using UnityEditor;
using System.IO;
using UnityEditor.Callbacks;
using UnityEditor.iOS.Xcode;

public class Sample_SetBaseReferenceForConfig  
{
    [PostProcessBuild]
    public static void OnPostprocessBuild(BuildTarget buildTarget, string pathToBuiltProject)
    {

        // Stop processing if build target is not iOS
        if (buildTarget != BuildTarget.iOS)
            return;

        // Initialize PBXProject
        string projectPath = PBXProject.GetPBXProjectPath(pathToBuiltProject);
        PBXProject pbxProject = new PBXProject();
        pbxProject.ReadFromFile(projectPath);

        // Get the target GUID
        string mainTargetGuid = pbxProject.GetUnityMainTargetGuid();

        // Retrieve the configuration name (this can be "Debug", "Release", or any custom configuration name)
        string configName = "Release";

        // Get the "Release" build configuration GUID 
        string configGuid = pbxProject.BuildConfigByName(mainTargetGuid, configName);

        // Add the file you will be using as base reference for the "Release" configuration
        // This example expects you having a "release.xcconfig" file in your project's "AssetsResources" directory
        string filePath = Path.Combine(Application.dataPath, "Resources/release.xcconfig");
        string file = pbxProject.AddFile(filePath, "Configs/release.xcconfig", PBXSourceTree.Source);

        // Set the base configuration file using SetBaseReferenceForConfig
        pbxProject.SetBaseReferenceForConfig(configGuid, file);

        // Apply changes to the pbxproj file
        pbxProject.WriteToFile(projectPath);
    }
}
```