{"id":42700,"date":"2024-11-13T20:47:58","date_gmt":"2024-11-13T20:47:58","guid":{"rendered":"https:\/\/atmokpo.com\/w\/?p=42700"},"modified":"2024-11-26T06:34:44","modified_gmt":"2024-11-26T06:34:44","slug":"2-c-%ec%b5%9c%ec%8b%a0-%eb%ac%b8%eb%b2%95%ea%b3%bc-%ea%b8%b0%eb%8a%a5-%ed%99%9c%ec%9a%a9-null-%ec%b2%98%eb%a6%ac-%ed%96%a5%ec%83%81nullable-reference-types","status":"publish","type":"post","link":"https:\/\/atmokpo.com\/w\/42700\/","title":{"rendered":"[\uac1d\uccb4\uc9c0\ud5a5] 2.C# \ucd5c\uc2e0 \ubb38\ubc95\uacfc \uae30\ub2a5 \ud65c\uc6a9, null \ucc98\ub9ac \ud5a5\uc0c1(Nullable Reference Types)"},"content":{"rendered":"
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\n C#\uc740 2000\ub144\ub300 \ucd08\ubc18\ubd80\ud130 \ubc1c\uc804\uc744 \uac70\ub4ed\ud558\uc5ec \uc624\ub298\ub0a0 \uac00\uc7a5 \uac15\ub825\ud55c \ud504\ub85c\uadf8\ub798\ubc0d \uc5b8\uc5b4 \uc911 \ud558\ub098\ub85c \uc790\ub9ac\uc7a1\uc558\uc2b5\ub2c8\ub2e4. \ucd5c\uc2e0 \ubc84\uc804\uc778 C# 8.0\uc5d0\uc11c \ub3c4\uc785\ub41c Nullable Reference Types\ub294 \uac1d\uccb4\uc9c0\ud5a5 \ud504\ub85c\uadf8\ub798\ubc0d\uacfc \ub514\uc790\uc778 \ud328\ud134 \ubd84\uc57c\uc5d0\uc11c \uc911\uc694\ud55c \ubcc0\ud654\ub97c \uac00\uc838\uc654\uc2b5\ub2c8\ub2e4. \uc774 \uae00\uc5d0\uc11c\ub294 C#\uc758 \ucd5c\uc2e0 \ubb38\ubc95\uacfc \uae30\ub2a5, \ud2b9\ud788 Nullable Reference Types\uc5d0 \ub300\ud574 \uae4a\uc774 \uc788\ub294 \ubd84\uc11d\uacfc \uc608\uc81c\ub97c \uc81c\uacf5\ud558\uace0\uc790 \ud569\ub2c8\ub2e4.\n <\/p>\n

1. Nullable Reference Types\ub780?<\/h2>\n

\n \uc77c\ubc18\uc801\uc73c\ub85c C#\uc5d0\uc11c\ub294 \ucc38\uc870\ud615 \ubcc0\uc218(Reference Type)\uac00 null \uac12\uc744 \uac00\uc9c8 \uc218 \uc788\uc2b5\ub2c8\ub2e4. \uc774\ub294 \ud504\ub85c\uadf8\ub7a8\uc5d0\uc11c NullReferenceException\uacfc \uac19\uc740 \uc624\ub958\ub97c \ubc1c\uc0dd\uc2dc\ud0a4\ub294 \uc8fc\uc694 \uc6d0\uc778 \uc911 \ud558\ub098\uc785\ub2c8\ub2e4. Nullable Reference Types\ub294 \uc774\ub7ec\ud55c \ubb38\uc81c\ub97c \ud574\uacb0\ud558\uae30 \uc704\ud574 C# 8.0\uc5d0\uc11c \ub3c4\uc785\ub41c \uae30\ub2a5\uc73c\ub85c, \ucc38\uc870\ud615 \ubcc0\uc218\uac00 null\uc774 \ub420 \uc218 \uc788\ub294\uc9c0\ub97c \uba85\uc2dc\uc801\uc73c\ub85c \ud45c\ud604\ud560 \uc218 \uc788\ub3c4\ub85d \ub3c4\uc640\uc90d\ub2c8\ub2e4.\n <\/p>\n

\n \uae30\ubcf8\uc801\uc73c\ub85c C# 8.0 \uc774\uc0c1\uc5d0\uc11c\ub294 nullable \ucc38\uc870\ud615 \ubcc0\uc218\ub97c \uc0ac\uc6a9\ud558\uae30 \uc704\ud574 `?` \uc5f0\uc0b0\uc790\ub97c \uc0ac\uc6a9\ud569\ub2c8\ub2e4. \uc774 \uc5f0\uc0b0\uc790\ub294 \ud574\ub2f9 \ubcc0\uc218\uc5d0 null \uac12\uc774 \ud560\ub2f9\ub420 \uc218 \uc788\uc74c\uc744 \ub098\ud0c0\ub0c5\ub2c8\ub2e4. \ubc18\uba74, nullable\uc774 \uc544\ub2cc \ucc38\uc870\ud615 \ubcc0\uc218\ub294 null\uc744 \ud5c8\uc6a9\ud558\uc9c0 \uc54a\uc74c\uc744 \ub098\ud0c0\ub0b4\uba70, \uc774 \uacbd\uc6b0 \ucef4\ud30c\uc77c\ub7ec\uc5d0\uc11c \uacbd\uace0\ub97c \ubc1c\uc0dd\uc2dc\ud0b5\ub2c8\ub2e4.\n <\/p>\n

\uc608\uc81c 1: Nullable Reference Types \uc0ac\uc6a9\ud558\uae30<\/h3>\n
\n        \npublic class Person\n{\n    public string Name { get; set; } \/\/ Non-nullable reference type\n    public string? Nickname { get; set; } \/\/ Nullable reference type\n}\n\npublic class Program\n{\n    public static void Main()\n    {\n        Person person = new Person();\n        person.Name = \"John Doe\";\n        person.Nickname = null; \/\/ OK\n\n        \/\/ Non-nullable reference type can't be set to null\n        \/\/ person.Name = null; \/\/ Error: Cannot convert null to 'string' because it is a non-nullable reference type\n    }\n}\n        <\/code>\n    <\/pre>\n
2. Nullable Reference Types\uc5d0\uc11c null \ucc98\ub9ac\ud558\uae30<\/h2>\n
\n        Nullable Reference Types\ub97c \uc0ac\uc6a9\ud558\uba74 \ucc38\uc870\ud615 \ubcc0\uc218\uc758 null \ucc98\ub9ac\uc5d0 \ub300\ud55c \uba85\ud655\ud55c \uc815\ucc45\uc744 \uc218\ub9bd\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4. \uc774 \uae30\ub2a5\uc740 \ucf54\ub4dc\uc5d0 \ub300\ud55c \uac00\ub3c5\uc131\uc744 \ub192\uc774\uace0, \uc7a0\uc7ac\uc801\uc778 NullReferenceException\uc744 \ubc29\uc9c0\ud558\ub294 \ub370 \ud070 \ub3c4\uc6c0\uc774 \ub429\ub2c8\ub2e4. null \ucc98\ub9ac\ub97c \uc704\ud574 \ub2e4\uc591\ud55c \uc811\uadfc \ubc29\uc2dd\uc744 \uc0ac\uc6a9\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.\n    <\/p>\n
Nullable \uc5f0\uc0b0\uc790 \uc0ac\uc6a9\ud558\uae30<\/h3>\n
\n        C#\uc5d0\uc11c\ub294 null \ubcd1\ud569 \uc5f0\uc0b0\uc790(`??`)\uc640 null \uc870\uac74 \uc5f0\uc0b0\uc790(`?.`)\ub97c \ud1b5\ud574 \uac04\ud3b8\ud558\uac8c null \ucc98\ub9ac\ub97c \ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4. null \ubcd1\ud569 \uc5f0\uc0b0\uc790\ub294 \uc67c\ucabd \uac12\uc774 null\uc77c \uacbd\uc6b0 \uc624\ub978\ucabd \uac12\uc744 \ubc18\ud658\ud558\ub294 \uc5f0\uc0b0\uc790\uc785\ub2c8\ub2e4. null \uc870\uac74 \uc5f0\uc0b0\uc790\ub294 \uac1d\uccb4\uac00 null\uc774 \uc544\ub2d0 \ub54c\ub9cc \ud574\ub2f9 \uc18d\uc131\uc774\ub098 \uba54\uc11c\ub4dc\uc5d0 \uc811\uadfc\ud560 \uc218 \uc788\uac8c \ud574\uc90d\ub2c8\ub2e4.\n    <\/p>\n
\uc608\uc81c 2: Null \ubcd1\ud569 \uc5f0\uc0b0\uc790 \uc0ac\uc6a9\ud558\uae30<\/h4>\n
\n        \npublic class Example\n{\n    public static void Main()\n    {\n        string? firstName = null;\n        string lastName = \"Doe\";\n\n        \/\/ Using null coalescing operator\n        string fullName = firstName ?? \"John\" + \" \" + lastName;\n        Console.WriteLine(fullName); \/\/ Output: John Doe\n    }\n}\n        <\/code>\n    <\/pre>\n
\uc608\uc81c 3: Null \uc870\uac74 \uc5f0\uc0b0\uc790 \uc0ac\uc6a9\ud558\uae30<\/h4>\n
\n        \npublic class User\n{\n    public string? Address { get; set; }\n}\n\npublic class Example\n{\n    public static void Main()\n    {\n        User user = new User();\n\n        \/\/ Using null conditional operator\n        int length = user.Address?.Length ?? 0; \/\/ Safe access to Address.Length\n        Console.WriteLine(length); \/\/ Output: 0\n    }\n}\n        <\/code>\n    <\/pre>\n
3. \ucef4\ud30c\uc77c\ub7ec \uacbd\uace0\uc640 Fluent API<\/h2>\n
\n        Nullable Reference Types\ub97c \uc0ac\uc6a9\ud558\uac8c \ub418\uba74 C# \ucef4\ud30c\uc77c\ub7ec\ub294 null \uac00\ub2a5\uc131\uc5d0 \ub300\ud574 \uacbd\uace0\ub97c \ud574\uc90d\ub2c8\ub2e4. \ub530\ub77c\uc11c, \uac1c\ubc1c\uc790\ub294 \ucf54\ub4dc\uc758 \uc548\uc804\uc131\uc5d0 \ub300\ud574 \ubcf4\ub2e4 \uc27d\uac8c \ud30c\uc545\ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4. \uc774\ub7ec\ud55c \uae30\ub2a5\uc740 \ud2b9\ud788 \ub300\uaddc\ubaa8 \ud504\ub85c\uc81d\ud2b8\uc5d0\uc11c \ud488\uc9c8 \ubcf4\uc99d\uc744 \uac15\ud654\ud558\ub294 \ub370 \ub3c4\uc6c0\uc774 \ub429\ub2c8\ub2e4.\n    <\/p>\n
\n        \ub610\ud55c, Nullable Reference Types\ub294 Fluent API\uc640 \ud568\uaed8 \uc0ac\uc6a9\ud560 \ub54c \ub9e4\uc6b0 \uac15\ub825\ud55c \ub3c4\uad6c\uac00 \ub429\ub2c8\ub2e4. Fluent API\ub294 \uba54\uc11c\ub4dc \uccb4\uc774\ub2dd\uc744 \ud1b5\ud574 \uac00\ub3c5\uc131\uc774 \ub192\uc740 \ucf54\ub4dc\ub97c \uc791\uc131\ud560 \uc218 \uc788\uac8c \ud574\uc90d\ub2c8\ub2e4. \ucc38\uc870\ud615 \ubcc0\uc218\ub97c \uc801\uc808\ud558\uac8c \ucc98\ub9ac\ud568\uc73c\ub85c\uc368, \uac1c\ubc1c\uc790\ub294 \ubcf4\ub2e4 \ud750\ub984 \uc788\ub294 \ucf54\ub4dc \uc791\uc131\uc744 \ud560 \uc218 \uc788\uc2b5\ub2c8\ub2e4.\n    <\/p>\n
\uc608\uc81c 4: Fluent API\uc640 \ud568\uaed8 \uc0ac\uc6a9\ud558\uae30<\/h4>\n
\n        \npublic class UserBuilder\n{\n    private string? name;\n    private string? email;\n\n    public UserBuilder SetName(string name)\n    {\n        this.name = name;\n        return this;\n    }\n\n    public UserBuilder SetEmail(string email)\n    {\n        this.email = email;\n        return this;\n    }\n\n    public User Build()\n    {\n        return new User { Name = name ?? \"Default Name\", Email = email };\n    }\n}\n\npublic class User\n{\n    public string Name { get; set; }\n    public string? Email { get; set; }\n}\n\npublic class Example\n{\n    public static void Main()\n    {\n        User user = new UserBuilder()\n            .SetName(\"John Doe\")\n            .SetEmail(null)\n            .Build();\n        \n        Console.WriteLine($\"Name: {user.Name}, Email: {user.Email ?? \"No Email\"}\");\n    }\n}\n        <\/code>\n    <\/pre>\n
4. Nullable Reference Types\uc758 \uc7a5\uc810<\/h2>\n
\n        Nullable Reference Types\ub97c \ud65c\uc6a9\ud558\uba74 \uc5ec\ub7ec \uac00\uc9c0 \uc7a5\uc810\uc744 \ub204\ub9b4 \uc218 \uc788\uc2b5\ub2c8\ub2e4. \uc8fc\uc694 \uc7a5\uc810\uc740 \ub2e4\uc74c\uacfc \uac19\uc2b5\ub2c8\ub2e4.\n    <\/p>\n