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//---------------------------------------------------------------------------
//
// Copyright (c) Microsoft Corporation. All rights reserved.
//
// Description: FontWeight structure.
//
// History:
// 01/25/2005 mleonov - Converted FontWeight from enum to a value type and moved it to a separate file.
//
//---------------------------------------------------------------------------
using System;
using System.ComponentModel;
using System.Diagnostics;
using SR=MS.Internal.PresentationCore.SR;
using SRID=MS.Internal.PresentationCore.SRID;
namespace System.Windows
{
/// <summary>
/// FontWeight structure describes the degree of blackness or thickness of strokes of characters in a font.
/// </summary>
[TypeConverter(typeof(FontWeightConverter))]
[Localizability(LocalizationCategory.None)]
public struct FontWeight : IFormattable
{
internal FontWeight(int weight)
{
Debug.Assert(1 <= weight && weight <= 999);
// We want the default zero value of new FontWeight() to correspond to FontWeights.Normal.
// Therefore, the _weight value is shifted by 400 relative to the OpenType weight value.
_weight = weight - 400;
}
/// <summary>
/// Creates a new FontWeight object that corresponds to the OpenType usWeightClass value.
/// </summary>
/// <param name="weightValue">An integer value between 1 and 999 that corresponds
/// to the usWeightClass definition in the OpenType specification.</param>
/// <returns>A new FontWeight object that corresponds to the weightValue parameter.</returns>
// Important note: when changing this method signature please make sure to update FontWeightConverter accordingly.
public static FontWeight FromOpenTypeWeight(int weightValue)
{
if (weightValue < 1 || weightValue > 999)
throw new ArgumentOutOfRangeException("weightValue", SR.Get(SRID.ParameterMustBeBetween, 1, 999));
return new FontWeight(weightValue);
}
/// <summary>
/// Obtains OpenType usWeightClass value that corresponds to the FontWeight object.
/// </summary>
/// <returns>An integer value between 1 and 999 that corresponds
/// to the usWeightClass definition in the OpenType specification.</returns>
// Important note: when changing this method signature please make sure to update FontWeightConverter accordingly.
public int ToOpenTypeWeight()
{
return RealWeight;
}
/// <summary>
/// Compares two font weight values and returns an indication of their relative values.
/// </summary>
/// <param name="left">First object to compare.</param>
/// <param name="right">Second object to compare.</param>
/// <returns>A 32-bit signed integer indicating the lexical relationship between the two comparands.
/// When the return value is less than zero this means that left is less than right.
/// When the return value is zero this means that left is equal to right.
/// When the return value is greater than zero this means that left is greater than right.
/// </returns>
public static int Compare(FontWeight left, FontWeight right)
{
return left._weight - right._weight;
}
/// <summary>
/// Checks whether a font weight is less than another.
/// </summary>
/// <param name="left">First object to compare.</param>
/// <param name="right">Second object to compare.</param>
/// <returns>True if left is less than right, false otherwise.</returns>
public static bool operator<(FontWeight left, FontWeight right)
{
return Compare(left, right) < 0;
}
/// <summary>
/// Checks whether a font weight is less or equal than another.
/// </summary>
/// <param name="left">First object to compare.</param>
/// <param name="right">Second object to compare.</param>
/// <returns>True if left is less or equal than right, false otherwise.</returns>
public static bool operator<=(FontWeight left, FontWeight right)
{
return Compare(left, right) <= 0;
}
/// <summary>
/// Checks whether a font weight is greater than another.
/// </summary>
/// <param name="left">First object to compare.</param>
/// <param name="right">Second object to compare.</param>
/// <returns>True if left is greater than right, false otherwise.</returns>
public static bool operator>(FontWeight left, FontWeight right)
{
return Compare(left, right) > 0;
}
/// <summary>
/// Checks whether a font weight is greater or equal than another.
/// </summary>
/// <param name="left">First object to compare.</param>
/// <param name="right">Second object to compare.</param>
/// <returns>True if left is greater or equal than right, false otherwise.</returns>
public static bool operator>=(FontWeight left, FontWeight right)
{
return Compare(left, right) >= 0;
}
/// <summary>
/// Checks whether two font weight objects are equal.
/// </summary>
/// <param name="left">First object to compare.</param>
/// <param name="right">Second object to compare.</param>
/// <returns>Returns true when the font weight values are equal for both objects,
/// and false otherwise.</returns>
public static bool operator==(FontWeight left, FontWeight right)
{
return Compare(left, right) == 0;
}
/// <summary>
/// Checks whether two font weight objects are not equal.
/// </summary>
/// <param name="left">First object to compare.</param>
/// <param name="right">Second object to compare.</param>
/// <returns>Returns false when the font weight values are equal for both objects,
/// and true otherwise.</returns>
public static bool operator!=(FontWeight left, FontWeight right)
{
return !(left == right);
}
/// <summary>
/// Checks whether the object is equal to another FontWeight object.
/// </summary>
/// <param name="obj">FontWeight object to compare with.</param>
/// <returns>Returns true when the object is equal to the input object,
/// and false otherwise.</returns>
public bool Equals(FontWeight obj)
{
return this == obj;
}
/// <summary>
/// Checks whether an object is equal to another character hit object.
/// </summary>
/// <param name="obj">FontWeight object to compare with.</param>
/// <returns>Returns true when the object is equal to the input object,
/// and false otherwise.</returns>
public override bool Equals(object obj)
{
if (!(obj is FontWeight))
return false;
return this == (FontWeight)obj;
}
/// <summary>
/// Compute hash code for this object.
/// </summary>
/// <returns>A 32-bit signed integer hash code.</returns>
public override int GetHashCode()
{
return RealWeight;
}
/// <summary>
/// Creates a string representation of this object based on the current culture.
/// </summary>
/// <returns>
/// A string representation of this object.
/// </returns>
public override string ToString()
{
// Delegate to the internal method which implements all ToString calls.
return ConvertToString(null, null);
}
/// <summary>
/// Creates a string representation of this object based on the format string
/// and IFormatProvider passed in.
/// If the provider is null, the CurrentCulture is used.
/// See the documentation for IFormattable for more information.
/// </summary>
/// <returns>
/// A string representation of this object.
/// </returns>
string IFormattable.ToString(string format, IFormatProvider provider)
{
// Delegate to the internal method which implements all ToString calls.
return ConvertToString(format, provider);
}
/// <summary>
/// Creates a string representation of this object based on the format string
/// and IFormatProvider passed in.
/// If the provider is null, the CurrentCulture is used.
/// See the documentation for IFormattable for more information.
/// </summary>
/// <returns>
/// A string representation of this object.
/// </returns>
private string ConvertToString(string format, IFormatProvider provider)
{
string convertedValue;
if (!FontWeights.FontWeightToString(RealWeight, out convertedValue))
{
// This can happen if _weight value is not a multiple of 100.
return RealWeight.ToString(provider);
}
return convertedValue;
}
/// <summary>
/// We want the default zero value of new FontWeight() to correspond to FontWeights.Normal.
/// Therefore, _weight value is shifted by 400 relative to the OpenType weight value.
/// </summary>
private int RealWeight
{
get
{
return _weight + 400;
}
}
private int _weight;
}
}
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