1

記入しやすくしたい構造体があります

    public struct DBParameter
    {
        public string parameterName;
        public object value;
        public DbType dbType;

        public DBParameter(string paramName, object val, DbType type)
        {
            parameterName = paramName;
            value = val;
            dbType = type;
        }
        public SqlParameter ToSqlParameter()
        {
            if (parameterName == string.Empty || parameterName == null)
                throw new ArgumentException("No parameter, fieldname is mandatory", "parameterName");

            SqlParameter me = new SqlParameter(parameterName, value);
            me.DbType = dbType;

            return me;
        }

そして、私はこのようなことを考えていました...

        public void LoadDBParameter<T>(string paramName, T val)
        {
            parameterName = paramName;
            value = val;
            if (val is Int32)
            {
                dbType = DbType.Int32;
            }
            if (val is String)
            {
                dbType = DbType.String;
            }
            if (val is Int64)
            {
                dbType = DbType.Int64;
            }
            if (true)
            {
                //(...)
            }
        }
    }

しかし、私は名前がほとんど同じであることを見てきました、可能なそれぞれの一般的なデータ構造体を書くよりもこれを行うためのより簡単な方法はありますか？

4

1 に答える 1

4

「dapper」からコードを盗むには、次のようにします。

    static readonly Dictionary<Type, DbType> typeMap;

    static SqlMapper()
    {
        typeMap = new Dictionary<Type, DbType>();
        typeMap[typeof(byte)] = DbType.Byte;
        typeMap[typeof(sbyte)] = DbType.SByte;
        typeMap[typeof(short)] = DbType.Int16;
        typeMap[typeof(ushort)] = DbType.UInt16;
        typeMap[typeof(int)] = DbType.Int32;
        typeMap[typeof(uint)] = DbType.UInt32;
        typeMap[typeof(long)] = DbType.Int64;
        typeMap[typeof(ulong)] = DbType.UInt64;
        typeMap[typeof(float)] = DbType.Single;
        typeMap[typeof(double)] = DbType.Double;
        typeMap[typeof(decimal)] = DbType.Decimal;
        typeMap[typeof(bool)] = DbType.Boolean;
        typeMap[typeof(string)] = DbType.String;
        typeMap[typeof(char)] = DbType.StringFixedLength;
        typeMap[typeof(Guid)] = DbType.Guid;
        typeMap[typeof(DateTime)] = DbType.DateTime;
        typeMap[typeof(DateTimeOffset)] = DbType.DateTimeOffset;
        typeMap[typeof(TimeSpan)] = DbType.Time;
        typeMap[typeof(byte[])] = DbType.Binary;
        typeMap[typeof(byte?)] = DbType.Byte;
        typeMap[typeof(sbyte?)] = DbType.SByte;
        typeMap[typeof(short?)] = DbType.Int16;
        typeMap[typeof(ushort?)] = DbType.UInt16;
        typeMap[typeof(int?)] = DbType.Int32;
        typeMap[typeof(uint?)] = DbType.UInt32;
        typeMap[typeof(long?)] = DbType.Int64;
        typeMap[typeof(ulong?)] = DbType.UInt64;
        typeMap[typeof(float?)] = DbType.Single;
        typeMap[typeof(double?)] = DbType.Double;
        typeMap[typeof(decimal?)] = DbType.Decimal;
        typeMap[typeof(bool?)] = DbType.Boolean;
        typeMap[typeof(char?)] = DbType.StringFixedLength;
        typeMap[typeof(Guid?)] = DbType.Guid;
        typeMap[typeof(DateTime?)] = DbType.DateTime;
        typeMap[typeof(DateTimeOffset?)] = DbType.DateTimeOffset;
        typeMap[typeof(TimeSpan?)] = DbType.Time;
        typeMap[typeof(Object)] = DbType.Object;
    }

    internal static DbType LookupDbType(Type type, string name)
    {
        DbType dbType;
        var nullUnderlyingType = Nullable.GetUnderlyingType(type);
        if (nullUnderlyingType != null) type = nullUnderlyingType;
        if (type.IsEnum)
        {
            type = Enum.GetUnderlyingType(type);
        }
        if (typeMap.TryGetValue(type, out dbType))
        {
            return dbType;
        }
        ... what to do if no match
    }
于 2012-11-05T20:40:07.943 に答える