Entity Framework\u3067\u5217\u6319\u4f53\u3092\u30e1\u30f3\u30d0\u30fc\u3068\u3057\u3066\u6301\u3064Entity\u3092\u30b3\u30fc\u30c9\u30d5\u30a1\u30fc\u30b9\u30c8\u306b\u3066\u3001\u30c6\u30fc\u30d6\u30eb\u3092\u4f5c\u6210\u3059\u308b\u3068\u3001\u5217\u6319\u4f53\u90e8\u5206\u306f\u6574\u6570(int)\u578b\u3068\u306a\u308b\u3002\u5217\u6319\u4f53\u4e2d\u306e\u4e26\u3073\u306b\u5909\u66f4\u304c\u7121\u3051\u308c\u3070\u554f\u984c\u306b\u306a\u3089\u306a\u3044\u306e\u3060\u304c\u3001DB\u306b\u5024\u3092\u4fdd\u5b58\u3057\u305f\u5f8c\u3067\u5217\u6319\u4f53\u306e\u9806\u756a\u304c\u5909\u66f4\u3055\u308c\u3066\u3057\u307e\u3046\u3068\u9f5f\u9f6c\u304c\u767a\u751f\u3059\u308b\u3002<\/p>\n\n\n\n
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\u3053\u306e\u3088\u3046\u306a\u5024\u5909\u63db\u3092\u884c\u3046\u306b\u306f\u3001DbContext\u304b\u3089\u6d3e\u751f\u3055\u305b\u305f\u30af\u30e9\u30b9\u3067\u3001OnModelCreating\u3092\u30aa\u30fc\u30d0\u30fc\u30e9\u30a4\u30c9\u3057\u3066\u3001Entity\u4e2d\u306e\u30d7\u30ed\u30d1\u30c6\u30a3\u306b\u3064\u3044\u3066\u5024\u30b3\u30f3\u30d0\u30fc\u30bf\u30fc\u3092\u5b9a\u7fa9\u3059\u308c\u3070\u3088\u3044\u3002<\/p>\n\n\n\n
\/\/ Alert Level\npublic enum AlertLevel { Debug, Information, Warning, Error, Fatal }\n\/\/ Message\npublic class AlertMessage {\n [Key]\n public int MessaegId { get; set; }\n public AlertLevel Level { get; set; }\n public string Message { get; set; } = null!;\n public DateTime LogDate { get; set; }\n}\n\/\/ DbContext\npublic class ConvTestCtx : DbContext {\n public DbSet<AlertMessage> Messages { get; set; } = null!;\n\t\t\u30fb\u30fb\u30fb\n protected override void OnModelCreating(ModelBuilder modelBuilder) {\n modelBuilder\n .Entity<AlertMessage>()\n .Property(e => e.Level)\n .HasConversion(\n v=>v.ToString(), \/\/ Instance\u21d2DB\n v=>(AlertLevel)Enum.Parse(typeof(AlertLevel),v) \/\/ DB\u21d2Instance\n );\n }\n}<\/code><\/pre><\/div>\n\n\n\n\u3053\u308c\u3067\u3001\u751f\u6210\u3055\u308c\u308b\u30c6\u30fc\u30d6\u30eb\u4f5c\u6210SQL\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3002<\/p>\n\n\n\n
CREATE TABLE [Messages] (\n [MessaegId] int NOT NULL IDENTITY,\n [Level] nvarchar(max) NOT NULL,\n [Message] nvarchar(max) NOT NULL,\n [LogDate] datetime2 NOT NULL,\n CONSTRAINT [PK_Messages] PRIMARY KEY ([MessaegId])\n);<\/code><\/pre><\/div>\n\n\n\n\u3054\u89a7\u306e\u3068\u304a\u308a\u3001Level\u304cnvarchar(max)\u3068\u306a\u3063\u3066\u3044\u308b\u3002\u5b9f\u969b\u306b\u767b\u9332\u3057\u305f\u7d50\u679c\u306f\u4ee5\u4e0b\u306e\u901a\u308a\u3002<\/p>\n\n\n\n
MessaegId Level\t Message \t LogDate\r\n5\t Information System has Started 2023\/03\/24 08:53:15\r\n6\t Warning Low Battery\t 2023\/03\/24 08:53:17\r\n7\t Debug\t Debug Message\t 2023\/03\/24 08:53:18\r<\/pre>\n\n\n\n\u3066\u306a\u611f\u3058\u3067\u3001\u53cc\u65b9\u5411\u306e\u578b\u5909\u63db\u304c\u53ef\u80fd\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
Entity Framework\u3067\u5217\u6319\u4f53\u3092\u30e1\u30f3\u30d0\u30fc\u3068\u3057\u3066\u6301\u3064Entity\u3092\u30b3\u30fc\u30c9 … \u7d9a\u304d\u3092\u8aad\u3080