Any character you need from any language is supported and will be the same character on any computer that supports Unicode. The universal encoding was dubbed “Unicode” by one of the people at Xerox that helped to create it. Before long, the concept of a universal character encoding that contained all the characters for all languages, became the obvious solution. In 1986, people working at Xerox and Apple both had different problems to solve that required the same solution. They didn 't make exchanging data with other operating systems any easier and mixing data with different encodings (typing a sentence in Japanese in the middle of an English-Language document, for example) was problematic. MacJapanese is a text encoding for files that store Japanese characters. MacRoman is a text encoding for files that use ASCII. Because there are so many characters, the character sets devised to support some of these languages use two bytes of data per character (rather than one byte per character, as in ASCII).Īpple eventually created various text encodings to make it easier to manage data. The problem is even worse for users of languages that don 't use the standard Roman alphabetic characters at all - like Japanese, Chinese, or Hebrew. Cross-platform applications have to build in some way of managing text that uses characters in the 128-255 range. However, the Macintosh and Windows extensions do not agree with one another. This enabled both operating systems to handle accented characters and other symbols that are not supported by the ASCII standard. When the Macintosh and Windows operating systems were introduced, each OS defined extensions to standard ASCII by defining codes from 128-255. Also, many languages (like French and German) use accented characters that are not defined as part of the ASCII specification. It doesn 't include special characters that are commonly used in typeset books such as curved quotes or the curved apostrophe, bullet characters, and long dashes-like this one. That covers what is available on an English-language typewriter, plus some special “control“ characters that can be used on computers to control output. The ASCII character set defines only 128 characters. Over the years, computers became more and more popular outside of the United States and ASCII started to show its weaknesses. In 1963 the American Standards Association (which later changed its name to the American National Standards Institute) announced the American Standard Code for Information Interchange (ASCII) which was based on the character set available on an English language typewriter. With a character set, information can be exchanged between computers made by different manufacturers. It is a mapping of letters, numbers, symbols, and invisible codes (like the carriage return or line feed) to numbers. A numbering scheme is sometimes called a character set. When the computer industry was in its infancy, each computer maker came up with their own numbering scheme. For example, "A" is ASCII character number 65. They store each character as a numeric code. If your app assumes the text was encoded as UTF-8 but it was in fact encoded as WindowsLatin1, then you may find that some characters do not display properly.Īs you know, computers don 't really store or understand characters. For these situations you need to understand how text encodings work and what changes you may need to make to your code to make sure it recognizes the text as it was encoded. If you are creating apps that open, create, or modify text files or data that are created outside of your app, then it's possible that the text was encoded using something other than UTF-8. If the strings you work with are created, saved, and read only within your own apps, you shouldn 't have to worry about encoding issues because the encoding used is stored along with the content of the string. In your Xojo projects, any Strings you create in code (as constants, variables, or literals) use the UTF-8 encoding, which is what is most commonly used today. In particular, the Unicode standard was designed to handle the encoding of any language and a mixture of languages in the same string. Over the years, ASCII was extended and other encodings were created to handle more and more characters and languages. You can use the String.ChrByte function to get the character that corresponds to a particular ASCII code value. These characters include only the upper and lowercase English alphabet, numbers, some symbols, and invisible control codes used in early computers. The oldest and most familiar encoding scheme is the ASCII encoding which defines 128 character codes (using Integer values 0-127). Reporting bugs and making feature requestsĪll computers use encoding systems to store character strings as a series of bytes.Searching text using the SoundEx algorithm.
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