代码如下，如有不足，麻烦请大佬评论区指出

        /// <summary>
        /// 获取指定命名空间下的类型名称
        /// </summary>
        /// <param name="_nameSpace">命名空间</param>
        /// <param name="typeName">类型名</param>
        /// <returns></returns>
        public static Type typen(string _nameSpace,string typeName)
        {
            Type type = null;
            try
            {
                Assembly[] assemblyArray = AppDomain.CurrentDomain.GetAssemblies();
                int assemblyArrayLength = assemblyArray.Length;
                for (int i = 0; i < assemblyArrayLength; ++i)
                {
                    type = assemblyArray[i].GetType(typeName);
                    if (type != null && String.Equals(type.Namespace, _nameSpace))
                    {
                        return type;
                    }
                }
                for (int i = 0; i < assemblyArrayLength; ++i)
                {
                    Type[] typeArray = assemblyArray[i].GetTypes().Where(t=> String.Equals(t.Namespace, _nameSpace,StringComparison.Ordinal)).ToArray();
                    int typeArrayLength = typeArray.Length;
                    for (int j = 0; j < typeArrayLength; ++j)
                    {
                        if (typeArray[j].Name.Equals(typeName))
                        {
                            return typeArray[j];
                        }
                    }
                }
            }
            catch (Exception)
            {
                LogShow.Log("获取类型失败");
            }
            return type;
        }