internal const int LookupThreshold = 5;

internal List<NpgsqlParameter> InternalList { get; } = new(5);

#if DEBUG

internal static bool TwoPassCompatMode;

#else

internal static readonly bool TwoPassCompatMode;

#endif

static NpgsqlParameterCollection()

=> TwoPassCompatMode = AppContext.TryGetSwitch("Npgsql.EnableLegacyCaseInsensitiveDbParameters", out var enabled)

&& enabled;

// Dictionary lookups for GetValue to improve performance. _caseSensitiveLookup is only ever used in legacy two-pass mode.

Dictionary<string, int>? _caseInsensitiveLookup;

Dictionary<string, int>? _caseSensitiveLookup;

/// <summary>

/// Initializes a new instance of the NpgsqlParameterCollection class.

/// </summary>

internal NpgsqlParameterCollection() { }

bool LookupEnabled => InternalList.Count >= LookupThreshold;

void LookupClear()

{

_caseInsensitiveLookup?.Clear();

_caseSensitiveLookup?.Clear();

}

void LookupAdd(string name, int index)

{

if (_caseInsensitiveLookup is null)

return;

if (TwoPassCompatMode)

_caseSensitiveLookup!.TryAdd(name, index);

_caseInsensitiveLookup.TryAdd(name, index);

}

void LookupInsert(string name, int index)

{

if (_caseInsensitiveLookup is null)

return;

if (TwoPassCompatMode &&

(!_caseSensitiveLookup!.TryGetValue(name, out var indexCs) || index < indexCs))

{

for (var i = index + 1; i < InternalList.Count; i++)

{

var parameterName = InternalList[i].TrimmedName;

if (_caseSensitiveLookup.TryGetValue(parameterName, out var currentI) && currentI + 1 == i)

_caseSensitiveLookup[parameterName] = i;

}

_caseSensitiveLookup[name] = index;

}

if (!_caseInsensitiveLookup.TryGetValue(name, out var indexCi) || index < indexCi)

{

for (var i = index + 1; i < InternalList.Count; i++)

{

var parameterName = InternalList[i].TrimmedName;

if (_caseInsensitiveLookup.TryGetValue(parameterName, out var currentI) && currentI + 1 == i)

_caseInsensitiveLookup[parameterName] = i;

}

_caseInsensitiveLookup[name] = index;

}

}

void LookupRemove(string name, int index)

{

if (_caseInsensitiveLookup is null)

return;

if (TwoPassCompatMode && _caseSensitiveLookup!.Remove(name))

{

for (var i = index; i < InternalList.Count; i++)

{

var parameterName = InternalList[i].TrimmedName;

if (_caseSensitiveLookup.TryGetValue(parameterName, out var currentI) && currentI - 1 == i)

_caseSensitiveLookup[parameterName] = i;

}

}

if (_caseInsensitiveLookup.Remove(name))

{

for (var i = index; i < InternalList.Count; i++)

{

var parameterName = InternalList[i].TrimmedName;

if (_caseInsensitiveLookup.TryGetValue(parameterName, out var currentI) && currentI - 1 == i)

_caseInsensitiveLookup[parameterName] = i;

}

// Fix-up the case-insensitive lookup to point to the next match, if any.

for (var i = 0; i < InternalList.Count; i++)

{

var value = InternalList[i];

if (string.Equals(name, value.TrimmedName, StringComparison.OrdinalIgnoreCase))

{

_caseInsensitiveLookup[value.TrimmedName] = i;

break;

}

}

}

}

void LookupChangeName(NpgsqlParameter parameter, string oldName, string oldTrimmedName, int index)

{

if (string.Equals(oldTrimmedName, parameter.TrimmedName, StringComparison.OrdinalIgnoreCase))

return;

if (oldName.Length != 0)

LookupRemove(oldTrimmedName, index);

if (!parameter.IsPositional)

LookupAdd(parameter.TrimmedName, index);

}

internal void ChangeParameterName(NpgsqlParameter parameter, string? value)

{

var oldName = parameter.ParameterName;

var oldTrimmedName = parameter.TrimmedName;

parameter.ChangeParameterName(value);

if (_caseInsensitiveLookup is null)

return;

var index = IndexOf(parameter);

if (index == -1) // This would be weird.

return;

LookupChangeName(parameter, oldName, oldTrimmedName, index);

}

#region NpgsqlParameterCollection Member

/// <summary>

/// Gets the <see cref="NpgsqlParameter"/> with the specified name.

/// </summary>

/// <param name="parameterName">The name of the <see cref="NpgsqlParameter"/> to retrieve.</param>

/// <value>

/// The <see cref="NpgsqlParameter"/> with the specified name, or a <see langword="null"/> reference if the parameter is not found.

/// </value>

public new NpgsqlParameter this[string parameterName]

{

get

{

ArgumentNullException.ThrowIfNull(parameterName);

var index = IndexOf(parameterName);

if (index == -1)

ThrowHelper.ThrowArgumentException("Parameter not found");

return InternalList[index];

}

set

{

ArgumentNullException.ThrowIfNull(parameterName);

ArgumentNullException.ThrowIfNull(value);

var index = IndexOf(parameterName);

if (index == -1)

ThrowHelper.ThrowArgumentException("Parameter not found");

if (!string.Equals(parameterName, value.TrimmedName, StringComparison.OrdinalIgnoreCase))

ThrowHelper.ThrowArgumentException("Parameter name must be a case-insensitive match with the property 'ParameterName' on the given NpgsqlParameter", nameof(parameterName));

var oldValue = InternalList[index];

LookupChangeName(value, oldValue.ParameterName, oldValue.TrimmedName, index);

InternalList[index] = value;

}

}

/// <summary>

/// Gets the <see cref="NpgsqlParameter"/> at the specified index.

/// </summary>

/// <param name="index">The zero-based index of the <see cref="NpgsqlParameter"/> to retrieve.</param>

/// <value>The <see cref="NpgsqlParameter"/> at the specified index.</value>

public new NpgsqlParameter this[int index]

{

get => InternalList[index];

set

{

ArgumentNullException.ThrowIfNull(value);

if (value.Collection is not null)

ThrowHelper.ThrowInvalidOperationException("The parameter already belongs to a collection");

var oldValue = InternalList[index];

if (ReferenceEquals(oldValue, value))

return;

LookupChangeName(value, oldValue.ParameterName, oldValue.TrimmedName, index);

InternalList[index] = value;

value.Collection = this;

oldValue.Collection = null;

}

}

/// <summary>

/// Adds the specified <see cref="NpgsqlParameter"/> object to the <see cref="NpgsqlParameterCollection"/>.

/// </summary>

/// <param name="value">The <see cref="NpgsqlParameter"/> to add to the collection.</param>

/// <returns>The parameter that was added.</returns>

public NpgsqlParameter Add(NpgsqlParameter value)

{

ArgumentNullException.ThrowIfNull(value);

if (value.Collection is not null)

ThrowHelper.ThrowInvalidOperationException("The parameter already belongs to a collection");

InternalList.Add(value);

value.Collection = this;

if (!value.IsPositional)

LookupAdd(value.TrimmedName, InternalList.Count - 1);

return value;

}

/// <inheritdoc />

void ICollection<NpgsqlParameter>.Add(NpgsqlParameter item)

=> Add(item);

/// <summary>

/// Adds a <see cref="NpgsqlParameter"/> to the <see cref="NpgsqlParameterCollection"/> given the specified parameter name and

/// value.

/// </summary>

/// <param name="parameterName">The name of the <see cref="NpgsqlParameter"/>.</param>

/// <param name="value">The value of the <see cref="NpgsqlParameter"/> to add to the collection.</param>

/// <returns>The parameter that was added.</returns>

public NpgsqlParameter AddWithValue(string parameterName, object value)

=> Add(new NpgsqlParameter(parameterName, value));

/// <summary>

/// Adds a <see cref="NpgsqlParameter"/> to the <see cref="NpgsqlParameterCollection"/> given the specified parameter name,

/// data type and value.

/// </summary>

/// <param name="parameterName">The name of the <see cref="NpgsqlParameter"/>.</param>

/// <param name="parameterType">One of the NpgsqlDbType values.</param>

/// <param name="value">The value of the <see cref="NpgsqlParameter"/> to add to the collection.</param>

/// <returns>The parameter that was added.</returns>

public NpgsqlParameter AddWithValue(string parameterName, NpgsqlDbType parameterType, object value)

=> Add(new NpgsqlParameter(parameterName, parameterType) { Value = value });

/// <summary>

/// Adds a <see cref="NpgsqlParameter"/> to the <see cref="NpgsqlParameterCollection"/> given the specified parameter name and

/// value.

/// </summary>

/// <param name="parameterName">The name of the <see cref="NpgsqlParameter"/>.</param>

/// <param name="value">The value of the <see cref="NpgsqlParameter"/> to add to the collection.</param>

/// <param name="parameterType">One of the <see cref="NpgsqlDbType"/> values.</param>

/// <param name="size">The length of the column.</param>

/// <returns>The parameter that was added.</returns>

public NpgsqlParameter AddWithValue(string parameterName, NpgsqlDbType parameterType, int size, object value)

=> Add(new NpgsqlParameter(parameterName, parameterType, size) { Value = value });

/// <summary>

/// Adds a <see cref="NpgsqlParameter"/> to the <see cref="NpgsqlParameterCollection"/> given the specified parameter name and

/// value.

/// </summary>

/// <param name="parameterName">The name of the <see cref="NpgsqlParameter"/>.</param>

/// <param name="value">The value of the <see cref="NpgsqlParameter"/> to add to the collection.</param>

/// <param name="parameterType">One of the <see cref="NpgsqlDbType"/> values.</param>

/// <param name="size">The length of the column.</param>

/// <param name="sourceColumn">The name of the source column.</param>

/// <returns>The parameter that was added.</returns>

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

=> Add(new NpgsqlParameter(parameterName, parameterType, size, sourceColumn) { Value = value });

/// <summary>

/// Adds a <see cref="NpgsqlParameter"/> to the <see cref="NpgsqlParameterCollection"/> given the specified value.

/// </summary>

/// <param name="value">The value of the <see cref="NpgsqlParameter"/> to add to the collection.</param>

/// <returns>The parameter that was added.</returns>

public NpgsqlParameter AddWithValue(object value)

=> Add(new NpgsqlParameter { Value = value });

/// <summary>

/// Adds a <see cref="NpgsqlParameter"/> to the <see cref="NpgsqlParameterCollection"/> given the specified data type and value.

/// </summary>

/// <param name="parameterType">One of the <see cref="NpgsqlDbType"/> values.</param>

/// <param name="value">The value of the <see cref="NpgsqlParameter"/> to add to the collection.</param>

/// <returns>The parameter that was added.</returns>

public NpgsqlParameter AddWithValue(NpgsqlDbType parameterType, object value)

=> Add(new NpgsqlParameter { NpgsqlDbType = parameterType, Value = value });

/// <summary>

/// Adds a <see cref="NpgsqlParameter"/> to the <see cref="NpgsqlParameterCollection"/> given the parameter name and the data type.

/// </summary>

/// <param name="parameterName">The name of the parameter.</param>

/// <param name="parameterType">One of the <see cref="DbType"/> values.</param>

/// <returns>The parameter that was added.</returns>

public NpgsqlParameter Add(string parameterName, NpgsqlDbType parameterType)

=> Add(new NpgsqlParameter(parameterName, parameterType));

/// <summary>

/// Adds a <see cref="NpgsqlParameter"/> to the <see cref="NpgsqlParameterCollection"/> with the parameter name, the data type,

/// and the column length.

/// </summary>

/// <param name="parameterName">The name of the parameter.</param>

/// <param name="parameterType">One of the <see cref="DbType"/> values.</param>

/// <param name="size">The length of the column.</param>

/// <returns>The parameter that was added.</returns>

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

=> Add(new NpgsqlParameter(parameterName, parameterType, size));

/// <summary>

/// Adds a <see cref="NpgsqlParameter"/> to the <see cref="NpgsqlParameterCollection"/> with the parameter name, the data type, the

/// column length, and the source column name.

/// </summary>

/// <param name="parameterName">The name of the parameter.</param>

/// <param name="parameterType">One of the <see cref="DbType"/> values.</param>

/// <param name="size">The length of the column.</param>

/// <param name="sourceColumn">The name of the source column.</param>

/// <returns>The parameter that was added.</returns>

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

=> Add(new NpgsqlParameter(parameterName, parameterType, size, sourceColumn));

#endregion

#region IDataParameterCollection Member

/// <inheritdoc />

// ReSharper disable once ImplicitNotNullOverridesUnknownExternalMember

public override void RemoveAt(string parameterName)

=> RemoveAt(IndexOf(parameterName ?? throw new ArgumentNullException(nameof(parameterName))));

/// <inheritdoc />

public override bool Contains(string parameterName)

=> IndexOf(parameterName ?? throw new ArgumentNullException(nameof(parameterName))) != -1;

/// <inheritdoc />

public override int IndexOf(string parameterName)

{

if (parameterName is null)

return -1;

if (parameterName.Length > 0 && (parameterName[0] == ':' || parameterName[0] == '@'))

parameterName = parameterName.Remove(0, 1);

// Using a dictionary is always faster after around 10 items when matched against reference equality.

// For string equality this is the case after ~3 items so we take a decent compromise going with 5.

if (LookupEnabled && parameterName.Length != 0)

{

if (_caseInsensitiveLookup is null)

BuildLookup();

if (TwoPassCompatMode && _caseSensitiveLookup!.TryGetValue(parameterName, out var indexCs))

return indexCs;

if (_caseInsensitiveLookup!.TryGetValue(parameterName, out var indexCi))

return indexCi;

return -1;

}

// Start with case-sensitive search in two pass mode.

if (TwoPassCompatMode)

{

for (var i = 0; i < InternalList.Count; i++)

{

var name = InternalList[i].TrimmedName;

if (string.Equals(parameterName, name))

return i;

}

}

// Then do case-insensitive search.

for (var i = 0; i < InternalList.Count; i++)

{

var name = InternalList[i].TrimmedName;

if (ReferenceEquals(parameterName, name) || string.Equals(parameterName, name, StringComparison.OrdinalIgnoreCase))

return i;

}

return -1;

void BuildLookup()

{

if (TwoPassCompatMode)

_caseSensitiveLookup = new Dictionary<string, int>(InternalList.Count);

_caseInsensitiveLookup = new Dictionary<string, int>(InternalList.Count, StringComparer.OrdinalIgnoreCase);

for (var i = 0; i < InternalList.Count; i++)

{

var item = InternalList[i];

if (!item.IsPositional)

LookupAdd(item.TrimmedName, i);

}

}

}

#endregion

#region IList Member

/// <inheritdoc />

public override bool IsReadOnly => false;

/// <summary>

/// Removes the specified <see cref="NpgsqlParameter"/> from the collection using a specific index.

/// </summary>

/// <param name="index">The zero-based index of the parameter.</param>

public override void RemoveAt(int index)

{

ArgumentOutOfRangeException.ThrowIfGreaterThanOrEqual(index, InternalList.Count);

Remove(InternalList[index]);

}

/// <summary>

/// Inserts a parameter into the <see cref="NpgsqlParameterCollection"/> at the specified index.

/// </summary>

/// <param name="index">The zero-based index at which to insert the parameter.</param>

/// <param name="value">The parameter to insert.</param>

/// <remarks>

/// Although this method accepts <see cref="object"/>, only instances of <see cref="NpgsqlParameter"/> are supported.

/// Passing any other type will result in an <see cref="InvalidCastException"/>.

/// </remarks>

public override void Insert(int index, object value)

=> Insert(index, Cast(value));

/// <summary>

/// Removes the <see cref="NpgsqlParameter"/> with the specified name from the collection.

/// </summary>

/// <param name="parameterName">The name of the <see cref="NpgsqlParameter"/> to remove from the collection.</param>

public void Remove(string parameterName)

{

ArgumentNullException.ThrowIfNull(parameterName);

var index = IndexOf(parameterName);

if (index < 0)

ThrowHelper.ThrowInvalidOperationException("No parameter with the specified name exists in the collection");

RemoveAt(index);

}

/// <summary>

/// Removes the specified <see cref="NpgsqlParameter"/> from the collection.

/// </summary>

/// <param name="value">The <see cref="NpgsqlParameter"/> to remove from the collection.</param>

/// <remarks>

/// Although this method accepts <see cref="object"/>, only instances of <see cref="NpgsqlParameter"/> are supported.

/// Passing any other type will result in an <see cref="InvalidCastException"/>.

/// </remarks>

public override void Remove(object value)

=> Remove(Cast(value));

/// <inheritdoc />

public override bool Contains(object value)

=> value is NpgsqlParameter param && InternalList.Contains(param);

/// <summary>

/// Gets a value indicating whether a <see cref="NpgsqlParameter"/> with the specified parameter name exists in the collection.

/// </summary>

/// <param name="parameterName">The name of the <see cref="NpgsqlParameter"/> object to find.</param>

/// <param name="parameter">

/// A reference to the requested parameter is returned in this out param if it is found in the list.

/// This value is <see langword="null"/> if the parameter is not found.

/// </param>

/// <returns>

/// <see langword="true"/> if the collection contains the parameter and param will contain the parameter;

/// otherwise, <see langword="false"/>.

/// </returns>

public bool TryGetValue(string parameterName, [NotNullWhen(true)] out NpgsqlParameter? parameter)

{

ArgumentNullException.ThrowIfNull(parameterName);

var index = IndexOf(parameterName);

if (index != -1)

{

parameter = InternalList[index];

return true;

}

parameter = null;

return false;

}

/// <summary>

/// Removes all items from the collection.

/// </summary>

public override void Clear()

{

// clean up parameters so they can be added to another command if required.

foreach (var toRemove in InternalList)

toRemove.Collection = null;

InternalList.Clear();

LookupClear();

}

/// <summary>

/// Returns the index of the specified parameter in the <see cref="NpgsqlParameterCollection"/>.

/// </summary>

/// <param name="value">The parameter to find.</param>

/// <returns>The index of the parameter if found; otherwise, -1.</returns>

/// <remarks>

/// Although this method accepts <see cref="object"/>, only instances of <see cref="NpgsqlParameter"/> are supported.

/// Passing any other type will result in an <see cref="InvalidCastException"/>.

/// </remarks>

public override int IndexOf(object value)

=> IndexOf(Cast(value));

/// <summary>

/// Adds a parameter to the <see cref="NpgsqlParameterCollection"/>.

/// </summary>

/// <param name="value">The parameter to add.</param>

/// <returns>The zero-based index at which the parameter was added.</returns>

/// <remarks>

/// Although this method accepts <see cref="object"/>, only instances of <see cref="NpgsqlParameter"/> are supported.

/// Passing any other type will result in an <see cref="InvalidCastException"/>.

/// To add a parameter by value, use <see cref="AddWithValue(object)"/>, <see cref="AddWithValue(string, object)"/>,

/// or one of the typed <see cref="Add(string, NpgsqlDbType)"/> overloads.

/// </remarks>

public override int Add(object value)

{

Add(Cast(value));

return Count - 1;

}

/// <inheritdoc />

public override bool IsFixedSize => false;

#endregion

#region ICollection Member

/// <inheritdoc />

public override bool IsSynchronized => (InternalList as ICollection).IsSynchronized;

/// <summary>

/// Gets the number of <see cref="NpgsqlParameter"/> objects in the collection.

/// </summary>

/// <value>The number of <see cref="NpgsqlParameter"/> objects in the collection.</value>

public override int Count => InternalList.Count;

/// <inheritdoc />

public override void CopyTo(Array array, int index)

=> ((ICollection)InternalList).CopyTo(array, index);

/// <inheritdoc />

bool ICollection<NpgsqlParameter>.IsReadOnly => false;

/// <inheritdoc />

public override object SyncRoot => ((ICollection)InternalList).SyncRoot;

#endregion

#region IEnumerable Member

IEnumerator<NpgsqlParameter> IEnumerable<NpgsqlParameter>.GetEnumerator()

=> InternalList.GetEnumerator();

/// <inheritdoc />

public override IEnumerator GetEnumerator() => InternalList.GetEnumerator();

#endregion

/// <summary>

/// Adds the elements of the specified array to the end of the <see cref="NpgsqlParameterCollection"/>.

/// </summary>

/// <param name="values">

/// An array of <see cref="object"/>s to add. Each item must be an instance of <see cref="NpgsqlParameter"/>.

/// Passing any other type will result in an <see cref="InvalidCastException"/>.

/// </param>

public override void AddRange(Array values)

{

ArgumentNullException.ThrowIfNull(values);

InternalList.EnsureCapacity(InternalList.Count + values.Length);

foreach (var parameter in values)

Add(Cast(parameter));

}

/// <inheritdoc />

protected override DbParameter GetParameter(string parameterName)

=> this[parameterName];

/// <inheritdoc />

protected override DbParameter GetParameter(int index)

=> this[index];

/// <inheritdoc />

protected override void SetParameter(string parameterName, DbParameter value)

=> this[parameterName] = Cast(value);

/// <inheritdoc />

protected override void SetParameter(int index, DbParameter value)

=> this[index] = Cast(value);

/// <summary>

/// Report the offset within the collection of the given parameter.

/// </summary>

/// <param name="item">Parameter to find.</param>

/// <returns>Index of the parameter, or -1 if the parameter is not present.</returns>

public int IndexOf(NpgsqlParameter item)

=> InternalList.IndexOf(item);

/// <summary>

/// Insert the specified parameter into the collection.

/// </summary>

/// <param name="index">Index of the existing parameter before which to insert the new one.</param>

/// <param name="item">Parameter to insert.</param>

public void Insert(int index, NpgsqlParameter item)

{

ArgumentNullException.ThrowIfNull(item);

if (item.Collection != null)

throw new Exception("The parameter already belongs to a collection");

InternalList.Insert(index, item);

item.Collection = this;

if (!item.IsPositional)

LookupInsert(item.TrimmedName, index);

}

/// <summary>

/// Report whether the specified parameter is present in the collection.

/// </summary>

/// <param name="item">Parameter to find.</param>

/// <returns>True if the parameter was found, otherwise false.</returns>

public bool Contains(NpgsqlParameter item) => InternalList.Contains(item);

/// <summary>

/// Remove the specified parameter from the collection.

/// </summary>

/// <param name="item">Parameter to remove.</param>

/// <returns>True if the parameter was found and removed, otherwise false.</returns>

public bool Remove(NpgsqlParameter item)

{

ArgumentNullException.ThrowIfNull(item);

if (item.Collection != this)

ThrowHelper.ThrowInvalidOperationException("The item does not belong to this collection");

var index = IndexOf(item);

if (index >= 0)

{

InternalList.RemoveAt(index);

if (!LookupEnabled)

LookupClear();

if (!item.IsPositional)

LookupRemove(item.TrimmedName, index);

item.Collection = null;

return true;

}

return false;

}

/// <summary>

/// Convert collection to a System.Array.

/// </summary>

/// <param name="array">Destination array.</param>

/// <param name="arrayIndex">Starting index in destination array.</param>

public void CopyTo(NpgsqlParameter[] array, int arrayIndex)

=> InternalList.CopyTo(array, arrayIndex);

/// <summary>

/// Convert collection to a System.Array.

/// </summary>

/// <returns>NpgsqlParameter[]</returns>

public NpgsqlParameter[] ToArray() => InternalList.ToArray();

internal void CloneTo(NpgsqlParameterCollection other)

{

other.InternalList.Clear();

foreach (var param in InternalList)

{

var newParam = param.Clone();

newParam.Collection = other;

other.InternalList.Add(newParam);

}

if (LookupEnabled && _caseInsensitiveLookup is not null)

{

other._caseInsensitiveLookup = new Dictionary<string, int>(_caseInsensitiveLookup, StringComparer.OrdinalIgnoreCase);

if (TwoPassCompatMode)

{

Debug.Assert(_caseSensitiveLookup is not null);

other._caseSensitiveLookup = new Dictionary<string, int>(_caseSensitiveLookup);

}

}

}

internal void ProcessParameters(NpgsqlDataSource.ReloadableState reloadableState, bool validateValues, CommandType commandType)

{

HasOutputParameters = false;

PlaceholderType = PlaceholderType.NoParameters;

var list = InternalList;

for (var i = 0; i < list.Count; i++)

{

var p = list[i];

switch (PlaceholderType)

{

case PlaceholderType.NoParameters:

PlaceholderType = p.IsPositional ? PlaceholderType.Positional : PlaceholderType.Named;

break;

case PlaceholderType.Named:

if (p.IsPositional)

PlaceholderType = PlaceholderType.Mixed;

break;

case PlaceholderType.Positional:

if (!p.IsPositional)

PlaceholderType = PlaceholderType.Mixed;

break;

case PlaceholderType.Mixed:

break;

default:

ThrowHelper.ThrowArgumentOutOfRangeException(nameof(PlaceholderType), $"Unknown {nameof(PlaceholderType)} value: {{0}}", PlaceholderType);

break;

}

switch (p.Direction)

{

case ParameterDirection.Input:

break;

case ParameterDirection.InputOutput:

if (PlaceholderType == PlaceholderType.Positional && commandType != CommandType.StoredProcedure)

ThrowHelper.ThrowNotSupportedException("Output parameters are not supported in positional mode (unless used with CommandType.StoredProcedure)");

HasOutputParameters = true;

break;

case ParameterDirection.Output:

if (PlaceholderType == PlaceholderType.Positional && commandType != CommandType.StoredProcedure)

ThrowHelper.ThrowNotSupportedException("Output parameters are not supported in positional mode (unless used with CommandType.StoredProcedure)");

HasOutputParameters = true;

continue;

case ParameterDirection.ReturnValue:

// Simply ignored

continue;

default:

ThrowHelper.ThrowArgumentOutOfRangeException(nameof(ParameterDirection),

$"Unhandled {nameof(ParameterDirection)} value: {{0}}", p.Direction);

break;

}

p.ResolveTypeInfo(reloadableState.SerializerOptions, reloadableState.DbTypeResolver, willBind: validateValues);

if (validateValues)

p.Bind(out _, out _);

}

}

internal bool HasOutputParameters { get; set; }

internal PlaceholderType PlaceholderType { get; set; }

static NpgsqlParameter Cast(object? value)

{

var castedValue = value as NpgsqlParameter;

if (castedValue is null)

ThrowInvalidCastException(value);

return castedValue;

}

[DoesNotReturn]

static void ThrowInvalidCastException(object? value) =>

throw new InvalidCastException(

$"The value \"{value}\" is not of type \"{nameof(NpgsqlParameter)}\" and cannot be used in this parameter collection.");

/// <summary>

/// The parameter collection includes no parameters.

/// </summary>

NoParameters,

/// <summary>

/// The parameter collection includes only named parameters.

/// </summary>

Named,

/// <summary>

/// The parameter collection includes only positional parameters.

/// </summary>

Positional,

/// <summary>

/// The parameter collection includes both named and positional parameters.

/// This is only supported when <see cref="NpgsqlCommand.CommandType" /> is set to <see cref="CommandType.StoredProcedure" />.

/// </summary>

Mixed