You can use concat in OCL when you need to append one string to another, for example when building display text or a message.

Syntax

stringExpression.concat(s)

concat has the following signature:

concat(s : String) : String

It returns a new string that contains the value of self followed by s.

Examples

Append text

The following expression appends ' world' to 'Hello':

'Hello'.concat(' world')

Result:

Hello world

Build a display value

If FirstName contains 'Ada' and LastName contains 'Lovelace', you can create a full name by concatenating the values and the separating space:

self.FirstName.concat(' ').concat(self.LastName)

Result:

Ada Lovelace

Notes

• concat appends text to the end of a string. Include any required separator, such as ' ', ', ', or '-', in the argument.
• The operation returns a string; it does not modify the original expression.
• Do not confuse concat, which operates on strings, with prepend, which adds an object to an OrderedSet.
• Use length when you need the number of characters in a string.

See also

• Documentation:OCL General Operators
• Documentation:OCLOperators length
• Documentation:OCLOperators prepend
• Documentation:OCLOperators let