Class NpgsqlParameter

Namespace

Npgsql

Assembly

Npgsql.dll

This class represents a parameter to a command that will be sent to server

public class NpgsqlParameter : DbParameter, IDbDataParameter, IDataParameter, ICloneable

Inheritance

object

MarshalByRefObject

DbParameter

NpgsqlParameter

Implements

IDbDataParameter

IDataParameter

ICloneable

Derived

NpgsqlParameter<T>

Inherited Members

MarshalByRefObject.GetLifetimeService()

MarshalByRefObject.InitializeLifetimeService()

MarshalByRefObject.MemberwiseClone(bool)

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Constructors

NpgsqlParameter()

Initializes a new instance of the NpgsqlParameter class.

public NpgsqlParameter()

NpgsqlParameter(string?, NpgsqlDbType)

Initializes a new instance of the NpgsqlParameter class with the parameter name and the data type.

public NpgsqlParameter(string? parameterName, NpgsqlDbType parameterType)

Parameters

parameterName string

The name of the parameter to map.

parameterType NpgsqlDbType

One of the NpgsqlDbType values.

NpgsqlParameter(string?, NpgsqlDbType, int)

Initializes a new instance of the NpgsqlParameter.

public NpgsqlParameter(string? parameterName, NpgsqlDbType parameterType, int size)

Parameters

parameterName string

The name of the parameter to map.

parameterType NpgsqlDbType

One of the NpgsqlDbType values.

size int

The length of the parameter.

NpgsqlParameter(string?, NpgsqlDbType, int, string?)

Initializes a new instance of the NpgsqlParameter

public NpgsqlParameter(string? parameterName, NpgsqlDbType parameterType, int size, string? sourceColumn)

Parameters

parameterName string

The name of the parameter to map.

parameterType NpgsqlDbType

One of the NpgsqlDbType values.

size int

The length of the parameter.

sourceColumn string

The name of the source column.

NpgsqlParameter(string, NpgsqlDbType, int, string?, ParameterDirection, bool, byte, byte, DataRowVersion, object)

Initializes a new instance of the NpgsqlParameter.

public NpgsqlParameter(string parameterName, NpgsqlDbType parameterType, int size, string? sourceColumn, ParameterDirection direction, bool isNullable, byte precision, byte scale, DataRowVersion sourceVersion, object value)

Parameters

parameterName string

The name of the parameter to map.

parameterType NpgsqlDbType

One of the NpgsqlDbType values.

size int

The length of the parameter.

sourceColumn string

The name of the source column.

direction ParameterDirection

One of the ParameterDirection values.

isNullable bool

true if the value of the field can be null, otherwise false.

precision byte

The total number of digits to the left and right of the decimal point to which Value is resolved.

scale byte

The total number of decimal places to which Value is resolved.

sourceVersion DataRowVersion

One of the DataRowVersion values.

value object

An object that is the value of the NpgsqlParameter.

NpgsqlParameter(string?, DbType)

Initializes a new instance of the NpgsqlParameter.

public NpgsqlParameter(string? parameterName, DbType parameterType)

Parameters

parameterName string

The name of the parameter to map.

parameterType DbType

One of the DbType values.

NpgsqlParameter(string?, DbType, int)

Initializes a new instance of the NpgsqlParameter.

public NpgsqlParameter(string? parameterName, DbType parameterType, int size)

Parameters

parameterName string

The name of the parameter to map.

parameterType DbType

One of the DbType values.

size int

The length of the parameter.

NpgsqlParameter(string?, DbType, int, string?)

Initializes a new instance of the NpgsqlParameter.

public NpgsqlParameter(string? parameterName, DbType parameterType, int size, string? sourceColumn)

Parameters

parameterName string

The name of the parameter to map.

parameterType DbType

One of the DbType values.

size int

The length of the parameter.

sourceColumn string

The name of the source column.

NpgsqlParameter(string, DbType, int, string?, ParameterDirection, bool, byte, byte, DataRowVersion, object)

Initializes a new instance of the NpgsqlParameter.

public NpgsqlParameter(string parameterName, DbType parameterType, int size, string? sourceColumn, ParameterDirection direction, bool isNullable, byte precision, byte scale, DataRowVersion sourceVersion, object value)

Parameters

parameterName string

The name of the parameter to map.

parameterType DbType

One of the DbType values.

size int

The length of the parameter.

sourceColumn string

The name of the source column.

direction ParameterDirection

One of the ParameterDirection values.

isNullable bool

true if the value of the field can be null, otherwise false.

precision byte

The total number of digits to the left and right of the decimal point to which Value is resolved.

scale byte

The total number of decimal places to which Value is resolved.

sourceVersion DataRowVersion

One of the DataRowVersion values.

value object

An object that is the value of the NpgsqlParameter.

NpgsqlParameter(string?, object?)

Initializes a new instance of the NpgsqlParameter class with the parameter name and a value.

public NpgsqlParameter(string? parameterName, object? value)

Parameters

parameterName string

The name of the parameter to map.

value object

The value of the NpgsqlParameter.

Remarks

When you specify an object in the value parameter, the DbType is inferred from the CLR type.

When using this constructor, you must be aware of a possible misuse of the constructor which takes a DbType parameter. This happens when calling this constructor passing an int 0 and the compiler thinks you are passing a value of DbType. Use ToInt32(object) for example to have compiler calling the correct constructor.

Properties

Collection

The collection to which this parameter belongs, if any.

public NpgsqlParameterCollection? Collection { get; set; }

Property Value

NpgsqlParameterCollection

DataTypeName

Used to specify which PostgreSQL type will be sent to the database for this parameter.

public string? DataTypeName { get; set; }

Property Value

string

DbType

Gets or sets the DbType of the parameter.

public override sealed DbType DbType { get; set; }

Property Value

DbType

One of the DbType values. The default is object.

Direction

Gets or sets a value that indicates whether the parameter is input-only, output-only, bidirectional, or a stored procedure return value parameter.

public override sealed ParameterDirection Direction { get; set; }

Property Value

ParameterDirection

One of the ParameterDirection values. The default is Input.

Exceptions

ArgumentException

The property is not set to one of the valid ParameterDirection values.

IsNullable

Gets or sets a value that indicates whether the parameter accepts null values.

public override sealed bool IsNullable { get; set; }

Property Value

bool

true if null values are accepted; otherwise false. The default is false.

NpgsqlDbType

Gets or sets the NpgsqlDbType of the parameter.

[DbProviderSpecificTypeProperty(true)]
public NpgsqlDbType NpgsqlDbType { get; set; }

Property Value

NpgsqlDbType

One of the NpgsqlDbType values. The default is NpgsqlDbType.

NpgsqlValue

Gets or sets the value of the parameter.

[TypeConverter(typeof(StringConverter))]
public object? NpgsqlValue { get; set; }

Property Value

object

An object that is the value of the parameter. The default value is null.

ParameterName

Gets or sets The name of the NpgsqlParameter.

public override sealed string ParameterName { get; set; }

Property Value

string

The name of the NpgsqlParameter. The default is an empty string.

PostgresType

The PostgreSQL data type, such as int4 or text, as discovered from pg_type. This property is automatically set if parameters have been derived via DeriveParameters(NpgsqlCommand) and can be used to acquire additional information about the parameters' data type.

public PostgresType? PostgresType { get; }

Property Value

PostgresType

Precision

Gets or sets the maximum number of digits used to represent the Value property.

public byte Precision { get; set; }

Property Value

byte

The maximum number of digits used to represent the Value property. The default value is 0, which indicates that the data provider sets the precision for Value.

Scale

Gets or sets the number of decimal places to which Value is resolved.

public byte Scale { get; set; }

Property Value

byte

The number of decimal places to which Value is resolved. The default is 0.

Size

Gets or sets the maximum size, in bytes, of the data within the column.

public override sealed int Size { get; set; }

Property Value

int

The maximum size, in bytes, of the data within the column. The default value is inferred from the parameter value.

SourceColumn

Gets or sets the name of the source column mapped to the DataSet and used for loading or returning the Value.

public override sealed string SourceColumn { get; set; }

Property Value

string

The name of the source column mapped to the DataSet. The default is an empty string.

SourceColumnNullMapping

Gets or sets a value which indicates whether the source column is nullable. This allows DbCommandBuilder to correctly generate Update statements for nullable columns.

public override sealed bool SourceColumnNullMapping { get; set; }

Property Value

bool

true if the source column is nullable; false if it is not.

SourceVersion

Gets or sets the DataRowVersion to use when you load Value.

public override sealed DataRowVersion SourceVersion { get; set; }

Property Value

DataRowVersion

One of the DataRowVersion values. The default is Current.

Exceptions

ArgumentException

The property is not set to one of the DataRowVersion values.

Value

Gets or sets the value of the parameter.

[TypeConverter(typeof(StringConverter))]
public override object? Value { get; set; }

Property Value

object

An object that is the value of the parameter. The default value is null.

Methods

Clone()

Creates a new NpgsqlParameter that is a copy of the current instance.

public NpgsqlParameter Clone()

Returns

NpgsqlParameter

A new NpgsqlParameter that is a copy of this instance.

ResetDbType()

Resets the DbType property to its original settings.

public override void ResetDbType()