/// <summary>
/// Render the enumerator argument into a string
/// </summary>
/// <param name="rendererMap">The map used to lookup renderers</param>
/// <param name="enumerator">the enumerator to render</param>
/// <param name="writer">The writer to render to</param>
/// <remarks>
/// <para>
/// Rendered as an open brace, followed by a comma
/// separated list of the elements (using the appropriate
/// renderer), followed by a close brace. For example:
/// <c>{a, b, c}</c>.
/// </para>
/// </remarks>
private void RenderEnumerator(RendererMap rendererMap, IEnumerator enumerator, TextWriter writer)
{
writer.Write("{");
if (enumerator != null && enumerator.MoveNext())
{
rendererMap.FindAndRender(enumerator.Current, writer);
while (enumerator.MoveNext())
{
writer.Write(", ");
rendererMap.FindAndRender(enumerator.Current, writer);
}
}
writer.Write("}");
}
/// <summary>
/// Render the array argument into a string
/// </summary>
/// <param name="rendererMap">The map used to lookup renderers</param>
/// <param name="array">the array to render</param>
/// <param name="writer">The writer to render to</param>
/// <remarks>
/// <para>
/// For a one dimensional array this is the
/// array type name, an open brace, followed by a comma
/// separated list of the elements (using the appropriate
/// renderer), followed by a close brace. For example:
/// <c>int[] {1, 2, 3}</c>.
/// </para>
/// <para>
/// If the array is not one dimensional the
/// <c>Array.ToString()</c> is returned.
/// </para>
/// </remarks>
private void RenderArray(RendererMap rendererMap, Array array, TextWriter writer)
{
if (array.Rank != 1)
{
writer.Write(array.ToString());
}
else
{
writer.Write(array.GetType().Name + " {");
int len = array.Length;
if (len > 0)
{
rendererMap.FindAndRender(array.GetValue(0), writer);
for (int i = 1; i < len; i++)
{
writer.Write(", ");
rendererMap.FindAndRender(array.GetValue(i), writer);
}
}
writer.Write("}");
}
}
/// <summary>
/// Render the DictionaryEntry argument into a string
/// </summary>
/// <param name="rendererMap">The map used to lookup renderers</param>
/// <param name="entry">the DictionaryEntry to render</param>
/// <param name="writer">The writer to render to</param>
/// <remarks>
/// <para>
/// Render the key, an equals sign ('='), and the value (using the appropriate
/// renderer). For example: <c>key=value</c>.
/// </para>
/// </remarks>
private void RenderDictionaryEntry(RendererMap rendererMap, DictionaryEntry entry, TextWriter writer)
{
rendererMap.FindAndRender(entry.Key, writer);
writer.Write("=");
rendererMap.FindAndRender(entry.Value, writer);
}
/// <summary>
/// Render the object <paramref name="obj"/> to a string
/// </summary>
/// <param name="rendererMap">The map used to lookup renderers</param>
/// <param name="obj">The object to render</param>
/// <param name="writer">The writer to render to</param>
/// <remarks>
/// <para>
/// Render the object <paramref name="obj"/> to a string.
/// </para>
/// <para>
/// The <paramref name="rendererMap"/> parameter is
/// provided to lookup and render other objects. This is
/// very useful where <paramref name="obj"/> contains
/// nested objects of unknown type. The <see cref="RendererMap.FindAndRender(object)"/>
/// method can be used to render these objects.
/// </para>
/// <para>
/// The default renderer supports rendering objects to strings as follows:
/// </para>
/// <list type="table">
/// <listheader>
/// <term>Value</term>
/// <description>Rendered String</description>
/// </listheader>
/// <item>
/// <term><c>null</c></term>
/// <description>
/// <para>"(null)"</para>
/// </description>
/// </item>
/// <item>
/// <term><see cref="Array"/></term>
/// <description>
/// <para>
/// For a one dimensional array this is the
/// array type name, an open brace, followed by a comma
/// separated list of the elements (using the appropriate
/// renderer), followed by a close brace.
/// </para>
/// <para>
/// For example: <c>int[] {1, 2, 3}</c>.
/// </para>
/// <para>
/// If the array is not one dimensional the
/// <c>Array.ToString()</c> is returned.
/// </para>
/// </description>
/// </item>
/// <item>
/// <term><see cref="IEnumerable"/>, <see cref="ICollection"/> & <see cref="IEnumerator"/></term>
/// <description>
/// <para>
/// Rendered as an open brace, followed by a comma
/// separated list of the elements (using the appropriate
/// renderer), followed by a close brace.
/// </para>
/// <para>
/// For example: <c>{a, b, c}</c>.
/// </para>
/// <para>
/// All collection classes that implement <see cref="ICollection"/> its subclasses,
/// or generic equivalents all implement the <see cref="IEnumerable"/> interface.
/// </para>
/// </description>
/// </item>
/// <item>
/// <term><see cref="DictionaryEntry"/></term>
/// <description>
/// <para>
/// Rendered as the key, an equals sign ('='), and the value (using the appropriate
/// renderer).
/// </para>
/// <para>
/// For example: <c>key=value</c>.
/// </para>
/// </description>
/// </item>
/// <item>
/// <term>other</term>
/// <description>
/// <para><c>Object.ToString()</c></para>
/// </description>
/// </item>
/// </list>
/// </remarks>
public void RenderObject(RendererMap rendererMap, object obj, TextWriter writer)
{
if (rendererMap == null)
{
throw new ArgumentNullException("rendererMap");
}
if (obj == null)
{
writer.Write(SystemInfo.NullText);
return;
}
Array objArray = obj as Array;
if (objArray != null)
{
RenderArray(rendererMap, objArray, writer);
return;
}
// Test if we are dealing with some form of collection object
IEnumerable objEnumerable = obj as IEnumerable;
if (objEnumerable != null)
{
// Get a collection interface if we can as its .Count property may be more
// performant than getting the IEnumerator object and trying to advance it.
ICollection objCollection = obj as ICollection;
if (objCollection != null && objCollection.Count == 0)
{
writer.Write("{}");
return;
}
// This is a special check to allow us to get the enumerator from the IDictionary
// interface as this guarantees us DictionaryEntry objects. Note that in .NET 2.0
// the generic IDictionary<> interface enumerates KeyValuePair objects rather than
// DictionaryEntry ones. However the implementation of the plain IDictionary
// interface on the generic Dictionary<> still returns DictionaryEntry objects.
IDictionary objDictionary = obj as IDictionary;
if (objDictionary != null)
{
RenderEnumerator(rendererMap, objDictionary.GetEnumerator(), writer);
return;
}
RenderEnumerator(rendererMap, objEnumerable.GetEnumerator(), writer);
return;
}
IEnumerator objEnumerator = obj as IEnumerator;
if (objEnumerator != null)
{
RenderEnumerator(rendererMap, objEnumerator, writer);
return;
}
if (obj is DictionaryEntry)
{
RenderDictionaryEntry(rendererMap, (DictionaryEntry)obj, writer);
return;
}
string str = obj.ToString();
writer.Write((str == null) ? SystemInfo.NullText : str);
}
