DSInternals/Src/Microsoft.Database.Isam/FieldCollection.cs

304 lines
10 KiB
C#

// ---------------------------------------------------------------------------
// <copyright file="FieldCollection.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
// ---------------------------------------------------------------------------
// ---------------------------------------------------------------------
// <summary>
// </summary>
// ---------------------------------------------------------------------
namespace Microsoft.Database.Isam
{
using System;
using System.Collections;
using System.Globalization;
/// <summary>
/// A Field Collection represents the set of fields that are in a given
/// record. It can be used to efficiently navigate those fields.
/// </summary>
public class FieldCollection : DictionaryBase, IEnumerable
{
/// <summary>
/// The location
/// </summary>
private Location location;
/// <summary>
/// The read only
/// </summary>
private bool readOnly = false;
/// <summary>
/// Gets a value indicating whether this field collection cannot be changed.
/// </summary>
public bool IsReadOnly
{
get
{
return this.readOnly;
}
}
/// <summary>
/// Gets the names.
/// </summary>
/// <value>
/// The names.
/// </value>
public ICollection Names
{
get
{
return this.Dictionary.Keys;
}
}
/// <summary>
/// Gets or sets the location of the record that contained these fields.
/// </summary>
/// <value>
/// The location.
/// </value>
public Location Location
{
get
{
return this.location;
}
set
{
this.CheckReadOnly();
this.location = value;
}
}
/// <summary>
/// Gets a value indicating whether the <see cref="T:System.Collections.IDictionary" /> object has a fixed size.
/// </summary>
/// <returns>true if the <see cref="T:System.Collections.IDictionary" /> object has a fixed size; otherwise, false.</returns>
public bool IsFixedSize
{
get
{
return this.readOnly;
}
}
/// <summary>
/// Sets a value indicating whether [read only].
/// </summary>
/// <value>
/// <c>true</c> if [read only]; otherwise, <c>false</c>.
/// </value>
internal bool ReadOnly
{
set
{
this.readOnly = value;
}
}
/// <summary>
/// The field values for the specified column.
/// </summary>
/// <value>
/// The <see cref="FieldValueCollection"/>.
/// </value>
/// <param name="columnName">the name of the column whose field values are desired</param>
/// <returns>A <see cref="FieldValueCollection"/> object to access values of this column.</returns>
public FieldValueCollection this[string columnName]
{
get
{
return (FieldValueCollection)Dictionary[columnName.ToLower(CultureInfo.InvariantCulture)];
}
set
{
this.Dictionary[columnName.ToLower(CultureInfo.InvariantCulture)] = value;
}
}
/// <summary>
/// The field values for the specified column
/// </summary>
/// <value>
/// The <see cref="FieldValueCollection"/>.
/// </value>
/// <param name="column">the column ID whose field values are desired</param>
/// <returns>A <see cref="FieldValueCollection"/> object to access values of this column.</returns>
public FieldValueCollection this[Columnid column]
{
get
{
return (FieldValueCollection)Dictionary[column.Name.ToLower(CultureInfo.InvariantCulture)];
}
set
{
this.Dictionary[column.Name.ToLower(CultureInfo.InvariantCulture)] = value;
}
}
/// <summary>
/// Fetches an enumerator containing all the fields for this record.
/// </summary>
/// <returns>An enumerator containing all the fields for this record.</returns>
/// <remarks>
/// This is the type safe version that may not work in other CLR
/// languages.
/// </remarks>
public new RecordEnumerator GetEnumerator()
{
return new RecordEnumerator(Dictionary.GetEnumerator());
}
/// <summary>
/// Adds the specified values.
/// </summary>
/// <param name="values">The values.</param>
public void Add(FieldValueCollection values)
{
this.Dictionary.Add(values.Name.ToLower(CultureInfo.InvariantCulture), values);
}
/// <summary>
/// Returns whether the specifed column exists in the row.
/// </summary>
/// <param name="columnName">Name of the column.</param>
/// <returns>Whether the specifed column exists in the row.</returns>
public bool Contains(string columnName)
{
return this.Dictionary.Contains(columnName.ToLower(CultureInfo.InvariantCulture));
}
/// <summary>
/// Returns whether the specifed column exists in the row.
/// </summary>
/// <param name="column">The column.</param>
/// <returns>Whether the specifed column exists in the row.</returns>
public bool Contains(Columnid column)
{
return this.Dictionary.Contains(column.Name.ToLower(CultureInfo.InvariantCulture));
}
/// <summary>
/// Removes the specified column name.
/// </summary>
/// <param name="columnName">Name of the column.</param>
public void Remove(string columnName)
{
this.Dictionary.Remove(columnName.ToLower(CultureInfo.InvariantCulture));
}
/// <summary>
/// Removes the specified column.
/// </summary>
/// <param name="column">The column.</param>
public void Remove(Columnid column)
{
this.Dictionary.Remove(column.Name.ToLower(CultureInfo.InvariantCulture));
}
/// <summary>
/// Fetches an enumerator containing all the fields for this record
/// </summary>
/// <returns>
/// An <see cref="T:System.Collections.IEnumerator" /> object that can be used to iterate through the collection.
/// </returns>
/// <remarks>
/// This is the standard version that will work with other CLR
/// languages.
/// </remarks>
IEnumerator IEnumerable.GetEnumerator()
{
return (IEnumerator)this.GetEnumerator();
}
/// <summary>
/// Performs additional custom processes before clearing the contents of the <see cref="T:System.Collections.DictionaryBase" /> instance.
/// </summary>
protected override void OnClear()
{
this.CheckReadOnly();
}
/// <summary>
/// Performs additional custom processes before inserting a new element into the <see cref="T:System.Collections.DictionaryBase" /> instance.
/// </summary>
/// <param name="key">The key of the element to insert.</param>
/// <param name="value">The value of the element to insert.</param>
protected override void OnInsert(object key, object value)
{
this.CheckReadOnly();
}
/// <summary>
/// Performs additional custom processes before removing an element from the <see cref="T:System.Collections.DictionaryBase" /> instance.
/// </summary>
/// <param name="key">The key of the element to remove.</param>
/// <param name="value">The value of the element to remove.</param>
protected override void OnRemove(object key, object value)
{
this.CheckReadOnly();
}
/// <summary>
/// Performs additional custom processes before setting a value in the <see cref="T:System.Collections.DictionaryBase" /> instance.
/// </summary>
/// <param name="key">The key of the element to locate.</param>
/// <param name="oldValue">The old value of the element associated with <paramref name="key" />.</param>
/// <param name="newValue">The new value of the element associated with <paramref name="key" />.</param>
protected override void OnSet(object key, object oldValue, object newValue)
{
this.CheckReadOnly();
}
/// <summary>
/// Performs additional custom processes when validating the element with the specified key and value.
/// </summary>
/// <param name="key">The key of the element to validate.</param>
/// <param name="value">The value of the element to validate.</param>
/// <exception cref="System.ArgumentException">
/// key must be of type System.String;key
/// or
/// value must be of type FieldValueCollection;value
/// or
/// key must match value.Name;key
/// </exception>
protected override void OnValidate(object key, object value)
{
if (!(key is string))
{
throw new ArgumentException("key must be of type System.String", "key");
}
if (!(value is FieldValueCollection))
{
throw new ArgumentException("value must be of type FieldValueCollection", "value");
}
if (((string)key).ToLower(CultureInfo.InvariantCulture) != ((FieldValueCollection)value).Name.ToLower(CultureInfo.InvariantCulture))
{
throw new ArgumentException("key must match value.Name", "key");
}
}
/// <summary>
/// Checks the read only.
/// </summary>
/// <exception cref="System.NotSupportedException">this field collection cannot be changed</exception>
private void CheckReadOnly()
{
if (this.readOnly)
{
throw new NotSupportedException("this field collection cannot be changed");
}
}
}
}