30 lines
		
	
	
		
			905 B
		
	
	
	
		
			C#
		
	
	
	
	
	
			
		
		
	
	
			30 lines
		
	
	
		
			905 B
		
	
	
	
		
			C#
		
	
	
	
	
	
| using System;
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| using System.Linq;
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| using Microsoft.Extensions.Configuration;
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| 
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| namespace GerstITS.Examples.Api.Configurations
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| {
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|     public static class IConfigurationExtensions
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|     {
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|         #region Methods
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| 
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|         public static TEnum GetFlaggedEnum<TEnum>(this IConfiguration configuration, string key)
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|             where TEnum : struct, IConvertible
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|         {
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|             ThrowsAnExceptionIfTypeIsNotAnEnumeration<TEnum>();
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| 
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|             return (TEnum)(object)(configuration.GetSection(key)?
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|                     .Get<TEnum[]>() ?? Enumerable.Empty<TEnum>())
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|                 .Sum(i => (int)(object)i);
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|         }
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| 
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|         private static void ThrowsAnExceptionIfTypeIsNotAnEnumeration<TEnum>() where TEnum : struct, IConvertible
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|         {
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|             if (!typeof(TEnum).IsEnum)
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|                 throw new InvalidOperationException($"{typeof(TEnum)} is not supported.");
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|         }
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| 
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|         #endregion
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|     }
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| }
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