4.3: String Data Type
- Page ID
- 11255
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Technically, there is no string data type in the C++ programming language. However, the concept of a string data type makes it easy to handle strings of character data. A single character has some limitations. Many data items are not integers or floating-point values. The message Hi Mom! is a good example of a string. Thus, the need to handle a series of characters as a single piece of data (in English correctly called a datum).
In the "C" programming language all string were handled as an array of characters that end in an ASCII null character (the value 0 or the first character in the ASCII character code set). Associated with object oriented programming the string class has been added to C++ as a standard part of the programming language. This changed with the implementation with strings being stored as a length controlled item with a maximum length of 255 characters. Included in the C++ string class is the reserved word of string as if it were a data type. Some basics about strings include:
C++ Reserved Word | String |
Represent | Series of Characters (technically an array) |
Size | Varies in length |
Normal Signage | N/A |
Domain (Values Allowed) | Extended ASCII Character Code Set |
C++ syntax rule | Double quote marks for constants |
For now, we will address only the use of strings as constants. Most modern compliers that are part of an Integrated Development Environment (IDE) will color the source code to help the programmer see different features more readily. Beginning programmers will use string constants to send messages to the monitor. A typical line of C++ code:
cout << "Hi Mom!";
would have the "Hi Mom" colored (usually red) to emphasize that the item is a string.
Definitions
- string
- A series or array of characters as a single piece of data.