|
// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
#if RIBBON_IN_FRAMEWORK
namespace System.Windows.Controls.Ribbon
#else
namespace Microsoft.Windows.Controls.Ribbon
#endif
{
using System;
using System.ComponentModel;
using System.Globalization;
using MS.Internal;
using System.Diagnostics;
using System.ComponentModel.Design.Serialization;
using System.Reflection;
/// <summary>
/// A class used for converting between RibbonControlLengths and strings/numbers.
/// </summary>
public class RibbonControlLengthConverter : TypeConverter
{
#region Private Fields
// Note: keep this array in sync with the RibbonControlLengthUnitType enum
private static string[] _unitStrings = { "auto", "px", "items", "*" };
// this array contains strings for unit types that are not present in the RibbonControlLengthUnitType enum
static private string[] _pixelUnitStrings = { "in", "cm", "pt" };
static private double[] _pixelUnitFactors =
{
96.0, // Pixels per Inch
96.0 / 2.54, // Pixels per Centimeter
96.0 / 72.0, // Pixels per Point
};
#endregion
#region Public Methods
/// <summary>
/// Checks whether or not this class can convert from a given type.
/// </summary>
public override bool CanConvertFrom(ITypeDescriptorContext context, Type sourceType)
{
// We can only handle strings, integral and floating types.
TypeCode tc = Type.GetTypeCode(sourceType);
switch (tc)
{
case TypeCode.String:
case TypeCode.Decimal:
case TypeCode.Single:
case TypeCode.Double:
case TypeCode.Int16:
case TypeCode.Int32:
case TypeCode.Int64:
case TypeCode.UInt16:
case TypeCode.UInt32:
case TypeCode.UInt64:
return true;
default:
return false;
}
}
/// <summary>
/// Checks whether or not this class can convert to a given type.
/// </summary>
public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
{
return (destinationType == typeof(InstanceDescriptor) || destinationType == typeof(string));
}
/// <summary>
/// Attempts to convert to a RibbonControlLength from the given object.
/// </summary>
public override object ConvertFrom(ITypeDescriptorContext context, CultureInfo culture, object value)
{
if (value != null)
{
string stringValue = value as string;
if (stringValue != null)
{
return FromString(stringValue, culture);
}
else
{
// conversion from numeric type
double doubleValue;
RibbonControlLengthUnitType type;
doubleValue = Convert.ToDouble(value, culture);
if (double.IsNaN(doubleValue))
{
// this allows for conversion from Width / Height = "Auto"
doubleValue = 1.0;
type = RibbonControlLengthUnitType.Auto;
}
else
{
type = RibbonControlLengthUnitType.Pixel;
}
return new RibbonControlLength(doubleValue, type);
}
}
throw GetConvertFromException(value);
}
/// <summary>
/// Attempts to convert a RibbonControlLength instance to the given type.
/// </summary>
public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
{
ArgumentNullException.ThrowIfNull(destinationType);
if (value != null && value is RibbonControlLength)
{
RibbonControlLength length = (RibbonControlLength)value;
if (destinationType == typeof(string))
{
return ToString(length, culture);
}
if (destinationType == typeof(InstanceDescriptor))
{
ConstructorInfo ci = typeof(RibbonControlLength).GetConstructor(new Type[] { typeof(double), typeof(RibbonControlLengthUnitType) });
return new InstanceDescriptor(ci, new object[] { length.Value, length.RibbonControlLengthUnitType });
}
}
throw GetConvertToException(value, destinationType);
}
#endregion
#region Internal Methods
/// <summary>
/// Converts a RibbonControlLength instance to a String given the CultureInfo.
/// </summary>
internal static string ToString(RibbonControlLength length, CultureInfo cultureInfo)
{
switch (length.RibbonControlLengthUnitType)
{
// for Auto print out "Auto". value is always "1.0"
case RibbonControlLengthUnitType.Auto:
return "Auto";
case RibbonControlLengthUnitType.Item:
return Convert.ToString(length.Value, cultureInfo) + "items";
// Star has one special case when value is "1.0".
// in this case drop value part and print only "Star"
case RibbonControlLengthUnitType.Star:
return (DoubleUtil.IsOne(length.Value) ? "*" : Convert.ToString(length.Value, cultureInfo) + "*");
// for Pixel print out the numeric value. "px" can be omitted.
default:
return Convert.ToString(length.Value, cultureInfo);
}
}
/// <summary>
/// Parses a RibbonControlLength from a string given the CultureInfo.
/// </summary>
internal static RibbonControlLength FromString(string s, CultureInfo cultureInfo)
{
string goodString = s.Trim().ToLowerInvariant();
double value = 0.0;
RibbonControlLengthUnitType unit = RibbonControlLengthUnitType.Pixel;
int i;
int strLen = goodString.Length;
int strLenUnit = 0;
double unitFactor = 1.0;
// this is where we would handle trailing whitespace on the input string.
// peel [unit] off the end of the string
i = 0;
if (goodString == _unitStrings[i])
{
strLenUnit = _unitStrings[i].Length;
unit = (RibbonControlLengthUnitType)i;
}
else
{
for (i = 1; i < _unitStrings.Length; ++i)
{
// Note: this is NOT a culture specific comparison.
// this is by design: we want the same unit string table to work across all cultures.
if (goodString.EndsWith(_unitStrings[i], StringComparison.Ordinal))
{
strLenUnit = _unitStrings[i].Length;
unit = (RibbonControlLengthUnitType)i;
break;
}
}
}
// we couldn't match a real unit from RibbonControlLengthUnitTypes.
// try again with a converter-only unit (a pixel equivalent).
if (i >= _unitStrings.Length)
{
for (i = 0; i < _pixelUnitStrings.Length; ++i)
{
// Note: this is NOT a culture specific comparison.
// this is by design: we want the same unit string table to work across all cultures.
if (goodString.EndsWith(_pixelUnitStrings[i], StringComparison.Ordinal))
{
strLenUnit = _pixelUnitStrings[i].Length;
unitFactor = _pixelUnitFactors[i];
break;
}
}
}
// this is where we would handle leading whitespace on the input string.
// this is also where we would handle whitespace between [value] and [unit].
// check if we don't have a [value]. This is acceptable for certain UnitTypes.
if (strLen == strLenUnit && (unit == RibbonControlLengthUnitType.Auto || unit == RibbonControlLengthUnitType.Star))
{
value = 1;
}
// we have a value to parse.
else
{
Debug.Assert(unit == RibbonControlLengthUnitType.Pixel || unit == RibbonControlLengthUnitType.Item ||
DoubleUtil.AreClose(unitFactor, 1.0));
ReadOnlySpan<char> valueString = goodString.AsSpan(0, strLen - strLenUnit);
value = double.Parse(valueString, provider: cultureInfo) * unitFactor;
}
return new RibbonControlLength(value, unit);
}
#endregion
}
}
|