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    Class SingleHandler

    A type handler for the PostgreSQL real data type.

    Inheritance
    Object
    NpgsqlTypeHandler
    NpgsqlTypeHandler<Single>
    NpgsqlSimpleTypeHandler<Single>
    SingleHandler
    Implements
    INpgsqlTypeHandler<Single>
    INpgsqlSimpleTypeHandler<Single>
    INpgsqlSimpleTypeHandler<Double>
    Inherited Members
    NpgsqlSimpleTypeHandler<Single>.Read(NpgsqlReadBuffer, Int32, Boolean, FieldDescription)
    NpgsqlSimpleTypeHandler<Single>.Write(Single, NpgsqlWriteBuffer, NpgsqlLengthCache, NpgsqlParameter, Boolean, CancellationToken)
    NpgsqlSimpleTypeHandler<Single>.ValidateAndGetLength(Single, NpgsqlLengthCache, NpgsqlParameter)
    NpgsqlTypeHandler<Single>.ReadAsObject(NpgsqlReadBuffer, Int32, Boolean, FieldDescription)
    NpgsqlTypeHandler<Single>.GetFieldType(FieldDescription)
    NpgsqlTypeHandler<Single>.GetProviderSpecificFieldType(FieldDescription)
    NpgsqlTypeHandler<Single>.CreateArrayHandler(PostgresArrayType, ArrayNullabilityMode)
    NpgsqlTypeHandler<Single>.CreateRangeHandler(PostgresType)
    NpgsqlTypeHandler<Single>.CreateMultirangeHandler(PostgresMultirangeType)
    NpgsqlTypeHandler.PostgresType
    NpgsqlTypeHandler.Read<TAny>(NpgsqlReadBuffer, Int32, Boolean, FieldDescription)
    NpgsqlTypeHandler.Read<TAny>(NpgsqlReadBuffer, Int32, FieldDescription)
    NpgsqlTypeHandler.ReadCustom<TAny>(NpgsqlReadBuffer, Int32, Boolean, FieldDescription)
    NpgsqlTypeHandler.ValidateAndGetLength<TAny>(TAny, NpgsqlLengthCache, NpgsqlParameter)
    NpgsqlTypeHandler.ValidateAndGetLengthCustom<TAny>(TAny, NpgsqlLengthCache, NpgsqlParameter)
    NpgsqlTypeHandler.WriteWithLength<TAny>(TAny, NpgsqlWriteBuffer, NpgsqlLengthCache, NpgsqlParameter, Boolean, CancellationToken)
    NpgsqlTypeHandler.WriteWithLengthCustom<TAny>(TAny, NpgsqlWriteBuffer, NpgsqlLengthCache, NpgsqlParameter, Boolean, CancellationToken)
    NpgsqlTypeHandler.ValidateObjectAndGetLength(Object, NpgsqlLengthCache, NpgsqlParameter)
    NpgsqlTypeHandler.WriteObjectWithLength(Object, NpgsqlWriteBuffer, NpgsqlLengthCache, NpgsqlParameter, Boolean, CancellationToken)
    NpgsqlTypeHandler.CreateConversionButNoParamException(Type)
    Object.Equals(Object)
    Object.Equals(Object, Object)
    Object.GetHashCode()
    Object.GetType()
    Object.MemberwiseClone()
    Object.ReferenceEquals(Object, Object)
    Object.ToString()
    Namespace: Npgsql.Internal.TypeHandlers.NumericHandlers
    Assembly: Npgsql.dll
    Syntax
    public class SingleHandler : NpgsqlSimpleTypeHandler<float>, INpgsqlTypeHandler<float>, INpgsqlSimpleTypeHandler<float>, INpgsqlSimpleTypeHandler<double>
    Remarks

    See https://www.postgresql.org/docs/current/static/datatype-numeric.html.

    The type handler API allows customizing Npgsql's behavior in powerful ways. However, although it is public, it should be considered somewhat unstable, and may change in breaking ways, including in non-major releases. Use it at your own risk.

    Constructors

    SingleHandler(PostgresType)

    Declaration
    public SingleHandler(PostgresType pgType)
    Parameters
    Type Name Description
    PostgresType pgType

    Methods

    Read(NpgsqlReadBuffer, Int32, FieldDescription)

    Reads a value of type TDefault with the given length from the provided buffer, with the assumption that it is entirely present in the provided memory buffer and no I/O will be required.

    Declaration
    public override float Read(NpgsqlReadBuffer buf, int len, FieldDescription fieldDescription = null)
    Parameters
    Type Name Description
    NpgsqlReadBuffer buf

    The buffer from which to read.

    Int32 len

    The byte length of the value. The buffer might not contain the full length, requiring I/O to be performed.

    FieldDescription fieldDescription

    Additional PostgreSQL information about the type, such as the length in varchar(30).

    Returns
    Type Description
    Single

    The fully-read value.

    Overrides
    Npgsql.Internal.TypeHandling.NpgsqlSimpleTypeHandler<System.Single>.Read(Npgsql.Internal.NpgsqlReadBuffer, System.Int32, Npgsql.BackendMessages.FieldDescription)

    ValidateAndGetLength(Double, NpgsqlParameter)

    Responsible for validating that a value represents a value of the correct and which can be written for PostgreSQL - if the value cannot be written for any reason, an exception should be thrown. Also returns the byte length needed to write the value.

    Declaration
    public int ValidateAndGetLength(double value, NpgsqlParameter parameter)
    Parameters
    Type Name Description
    Double value
    NpgsqlParameter parameter

    The NpgsqlParameter instance where this value resides. Can be used to access additional information relevant to the write process (e.g. Size).

    Returns
    Type Description
    Int32

    The number of bytes required to write the value.

    ValidateAndGetLength(Single, NpgsqlParameter)

    Responsible for validating that a value represents a value of the correct and which can be written for PostgreSQL - if the value cannot be written for any reason, an exception shold be thrown. Also returns the byte length needed to write the value.

    Declaration
    public override int ValidateAndGetLength(float value, NpgsqlParameter parameter)
    Parameters
    Type Name Description
    Single value
    NpgsqlParameter parameter

    The NpgsqlParameter instance where this value resides. Can be used to access additional information relevant to the write process (e.g. Size).

    Returns
    Type Description
    Int32

    The number of bytes required to write the value.

    Overrides
    Npgsql.Internal.TypeHandling.NpgsqlSimpleTypeHandler<System.Single>.ValidateAndGetLength(System.Single, Npgsql.NpgsqlParameter)

    Write(Double, NpgsqlWriteBuffer, NpgsqlParameter)

    Writes a value to the provided buffer, with the assumption that there is enough space in the buffer (no I/O will occur). The Npgsql core will have taken care of that.

    Declaration
    public void Write(double value, NpgsqlWriteBuffer buf, NpgsqlParameter parameter)
    Parameters
    Type Name Description
    Double value
    NpgsqlWriteBuffer buf

    The buffer to which to write.

    NpgsqlParameter parameter

    The NpgsqlParameter instance where this value resides. Can be used to access additional information relevant to the write process (e.g. Size).

    Write(Single, NpgsqlWriteBuffer, NpgsqlParameter)

    Writes a value to the provided buffer, with the assumption that there is enough space in the buffer (no I/O will occur). The Npgsql core will have taken care of that.

    Declaration
    public override void Write(float value, NpgsqlWriteBuffer buf, NpgsqlParameter parameter)
    Parameters
    Type Name Description
    Single value
    NpgsqlWriteBuffer buf

    The buffer to which to write.

    NpgsqlParameter parameter

    The NpgsqlParameter instance where this value resides. Can be used to access additional information relevant to the write process (e.g. Size).

    Overrides
    Npgsql.Internal.TypeHandling.NpgsqlSimpleTypeHandler<System.Single>.Write(System.Single, Npgsql.Internal.NpgsqlWriteBuffer, Npgsql.NpgsqlParameter)

    Explicit Interface Implementations

    INpgsqlSimpleTypeHandler<Double>.Read(NpgsqlReadBuffer, Int32, FieldDescription)

    Declaration
    double INpgsqlSimpleTypeHandler<double>.Read(NpgsqlReadBuffer buf, int len, FieldDescription fieldDescription)
    Parameters
    Type Name Description
    NpgsqlReadBuffer buf
    Int32 len
    FieldDescription fieldDescription
    Returns
    Type Description
    Double

    Implements

    INpgsqlTypeHandler<T>
    INpgsqlSimpleTypeHandler<T>
    INpgsqlSimpleTypeHandler<T>
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