开发
通过C代码及函数指针回调方式：
iOS代码，在SDK中创建.mm文件：

#import <Foundation/Foundation.h>
#import <UIKit/UIKit.h>
#import "TWUnityBridgeSDK.h"

#if defined(__cplusplus)
extern "C"
{
#endif

///Unity调用iOS通用方法
extern void unityToiOS(const char* jsonStr);
///定义函数指针
typedef void(*CALLBACK_TOUnity)(const char*);
///iOS调用Unity通用函数指针对象
static CALLBACK_TOUnity callback_to_unity = nil;
///Unity注册回调方法
void iosCallBacktoUnity(CALLBACK_TOUnity callback);

#if defined(__cplusplus)
}
#endif

#ifdef DEBUG
#define NSLog(format, ...) printf("[%s] %s [第%d行] %s\n", __TIME__, __FUNCTION__, __LINE__, [[NSString stringWithFormat:format, ## __VA_ARGS__] UTF8String]);
#endif
///Unity调用iOS通用方法
void unityToiOS(const char* jsonStr)
{
    // 创建NSString从C字符串
    NSString* str = [NSString stringWithUTF8String:jsonStr];
    [TWUnityBridgeSDK unityToiOSWithJson:str callBackHandler:^(NSString *data, NSError *error) {
        if(callback_to_unity != nil) {
            NSLog(@"iOSToUnity=======---%@", data);
            char* commandchar = (char*) [data UTF8String];
            callback_to_unity(commandchar);  //字符串发给C#
        } else {
            NSLog(@"callback_to_unity为空=======444---%@", data);
        }
    }];
}

///Unity注册回调方法
void iosCallBacktoUnity(CALLBACK_TOUnity callback)
{
    callback_to_unity = callback;
    if (callback == nil) {
        NSLog(@"Unity注册回调失败=======");
    }
}

Unity代码

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using System.Runtime.InteropServices;
using AOT;

public class SDKIOS : MonoBehaviour
{
    [UnmanagedFunctionPointer(CallingConvention.Cdecl)]
    public delegate void callbackN0Delegate(IntPtr data);
    [DllImport("__Internal")]
    public static extern void iosCallBacktoUnity(IntPtr callback);

    [DllImport("__Internal")]
    private static  extern void unityToiOS(string str);

    // Start is called before the first frame update
    public void Start()
    {
        RegisterCallback();
      // 调用外部方法，传递字符串参数到iOS
        unityToiOS("{\"type\": 1, \"data\": {\"msg\": \"调用iOSSDK初始化\",\"appName\": \"兔玩\"}}");
    }
    
    public void testBtnClick()
    {   //测试跳转原生H5
        // unityToiOS("{\"type\": 3, \"data\": {\"url\": \"https://y-test.tuwan.com/activity/483Cea4771?v=1717391952164#/\", \"isPopView\":0}}");
        //测试调用原生支付
         unityToiOS("{\"type\":3,\"data\":\"{\\\"json\\\":\\\"{\\\\\\\"goodsId\\\\\\\":\\\\\\\"1000020\\\\\\\",\\\\\\\"orderNo\\\\\\\":\\\\\\\"51df30b7c41b4b02adb309a687ef1356\\\\\\\",\\\\\\\"orderToken\\\\\\\":\\\\\\\"67b36e731657f3627ade429e53cd42ab\\\\\\\",\\\\\\\"data\\\\\\\":{\\\\\\\"price\\\\\\\":18,\\\\\\\"bewrite\\\\\\\":\\\\\\\"126钻石\\\\\\\"},\\\\\\\"platform\\\\\\\":0,\\\\\\\"typeId\\\\\\\":2129}\\\",\\\"payPoint\\\":\\\"d_diandian2\\\"}\"}");
         //测试调用隐私协议弹窗
    }

    private void RegisterCallback()
    {
        callbackN0Delegate callbackN0_delegate = SendDataToGame;

        //将Delegate转换为非托管的函数指针
        IntPtr intptrN0_delegate = Marshal.GetFunctionPointerForDelegate(callbackN0_delegate);

        //调用非托管函数
        iosCallBacktoUnity(intptrN0_delegate);
    }

    //原生层发送数据到游戏层
    [MonoPInvokeCallback(typeof(callbackN0Delegate))]
    static void SendDataToGame(IntPtr data)
    {
        var dataStr = Marshal.PtrToStringAnsi(data);
        Debug.Log(dataStr);
    }
}