Provides information about the version of Unicode used to compare and order strings.
Assembly: mscorlib (in mscorlib.dll)
Thetype exposes the following members.
|Equals(Object)||Returns a value that indicates whether this instance is equal to a specified object. (Overrides Object.Equals(Object).)|
|Equals(SortVersion)||Returns a value that indicates whether this instance is equal to a specified object.|
|GetHashCode||Returns a hash code for this instance. (Overrides Object.GetHashCode().)|
|GetType||Gets the Type of the current instance. (Inherited from Object.)|
|ToString||Returns a string that represents the current object. (Inherited from Object.)|
From the .NET Framework 2.0 Service Pack 1 through the .NET Framework 4, each version of the.NET Framework has included tables that contain sort weights and data on string normalization and that are based on a particular version of Unicode. In the .NET Framework 4.5, the presence of these tables depends on the operating system:
On Windows 7 and previous versions of the Windows operating system, the tables continue to be used for comparing and ordering strings.
On Windows 8, the .NET Framework delegates string comparison and ordering operations to the operating system.
Consequently, the result of a string comparison can depend not only on the .NET Framework version, but also on the operating system version, as the following table shows.
.NET Framework version
.NET Framework 4
All operating systems
.NET Framework 4.5
.NET Framework 4.5
On Windows 8, because the version of Unicode used in string comparison and ordering depends on the version of the operating system, the results of string comparison may differ even for applications that run on a specific version of the .NET Framework.
The class provides information about the Unicode version used by the .NET Framework for string comparison and ordering. It enables developers to write applications that can detect and successfully handle changes in the version of Unicode that is used to compare and sort an application's strings.
You can instantiate a object in two ways:
By calling the SortVersion constructor, which instantiates a new object based on a version number and sort ID. This constructor is most useful when recreating a object from saved data.
By retrieving the value of the CompareInfo.Version property. This property provides information about the Unicode version used by the .NET Framework on which the application is running.
The class has two properties, FullVersion and SortId, that indicate the Unicode version and the specific culture used for string comparison. The FullVersion property is an arbitrary numeric value that reflects the Unicode version used for string comparison, and the SortId property is an arbitrary Guid that reflects the culture whose conventions are used for string comparison. The values of these two properties are important only when you compare two objects by using the Equals method, the Equality operator, or the Inequality operator.
You typically use a object when saving or retrieving some form of culture-sensitive, ordered string data, such as indexes or the literal strings themselves. This requires the following steps:
When the ordered string data is retrieved, you can recreate the object used for ordering the strings by calling the SortVersion constructor.
This newly instantiated object is compared with a object that reflects the culture whose conventions are used to order the string data.
If the two objects are not equal, the string data must be reordered.
The example provides an illustration.
The following example contains a portion of the source code from an application that uses the class to ensure that the native names of RegionInfo objects are ordered appropriately for the current system and current culture. It uses the BinaryReader and BinaryWriter objects to store and retrieve ordered data from a data file named Regions.dat rather than retrieving and ordering data each time the application is run. The example first checks to determine whether the data file exists. If it does not, it creates the data and sets the reindex flag, which indicates that the data must be resorted and saved again. Otherwise, it retrieves the data and compares the saved object with the object for the current culture on the current system. If they are not equal, or if the reindex flag had been set previously, it resorts the RegionInfo data.