Class ArrayHandler<TElement>
- Namespace
- Npgsql.TypeHandlers
- Assembly
- Npgsql.dll
Base class for all type handlers which handle PostgreSQL arrays.
public class ArrayHandler<TElement> : ArrayHandler
Type Parameters
TElement
- Inheritance
-
ArrayHandler<TElement>
- Inherited Members
Remarks
Constructors
ArrayHandler(NpgsqlTypeHandler, int)
public ArrayHandler(NpgsqlTypeHandler elementHandler, int lowerBound = 1)
Parameters
elementHandler
NpgsqlTypeHandlerlowerBound
int
Methods
ReadArray<T>(NpgsqlReadBuffer, bool)
protected ValueTask<Array> ReadArray<T>(NpgsqlReadBuffer buf, bool async)
Parameters
buf
NpgsqlReadBufferasync
bool
Returns
- ValueTask<Array>
Type Parameters
T
ReadList<T>(NpgsqlReadBuffer, bool)
protected ValueTask<List<T>> ReadList<T>(NpgsqlReadBuffer buf, bool async)
Parameters
buf
NpgsqlReadBufferasync
bool
Returns
- ValueTask<List<T>>
Type Parameters
T
Read<TAny>(NpgsqlReadBuffer, int, bool, FieldDescription)
Reads a value of type TAny
with the given length from the provided buffer,
using either sync or async I/O.
protected override ValueTask<TAny> Read<TAny>(NpgsqlReadBuffer buf, int len, bool async, FieldDescription fieldDescription = null)
Parameters
buf
NpgsqlReadBufferThe buffer from which to read.
len
intThe byte length of the value. The buffer might not contain the full length, requiring I/O to be performed.
async
boolIf I/O is required to read the full length of the value, whether it should be performed synchronously or asynchronously.
fieldDescription
FieldDescriptionAdditional PostgreSQL information about the type, such as the length in varchar(30).
Returns
- ValueTask<TAny>
The fully-read value.
Type Parameters
TAny
ValidateAndGetLength<TAny>(TAny, ref NpgsqlLengthCache, NpgsqlParameter)
Called to validate and get the length of a value of a generic NpgsqlParameter<T>.
protected override int ValidateAndGetLength<TAny>(TAny value, ref NpgsqlLengthCache lengthCache, NpgsqlParameter parameter)
Parameters
value
TAnylengthCache
NpgsqlLengthCacheparameter
NpgsqlParameter
Returns
Type Parameters
TAny
ValidateObjectAndGetLength(object, ref NpgsqlLengthCache, 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.
protected override int ValidateObjectAndGetLength(object value, ref NpgsqlLengthCache lengthCache, NpgsqlParameter parameter = null)
Parameters
value
objectThe value to be written to PostgreSQL
lengthCache
NpgsqlLengthCacheIf the byte length calculation is costly (e.g. for UTF-8 strings), its result can be stored in the length cache to be reused in the writing process, preventing recalculation.
parameter
NpgsqlParameterThe NpgsqlParameter instance where this value resides. Can be used to access additional information relevant to the write process (e.g. Size).
Returns
- int
The number of bytes required to write the value.
WriteObjectWithLength(object, NpgsqlWriteBuffer, NpgsqlLengthCache, NpgsqlParameter, bool)
Writes a value to the provided buffer, using either sync or async I/O.
protected override Task WriteObjectWithLength(object value, NpgsqlWriteBuffer buf, NpgsqlLengthCache lengthCache, NpgsqlParameter parameter, bool async)
Parameters
value
objectThe value to write.
buf
NpgsqlWriteBufferThe buffer to which to write.
lengthCache
NpgsqlLengthCacheparameter
NpgsqlParameterThe NpgsqlParameter instance where this value resides. Can be used to access additional information relevant to the write process (e.g. Size).
async
boolIf I/O is required to read the full length of the value, whether it should be performed synchronously or asynchronously.