Type Conversion in Informix 4GL

问题:

I want to convert a variable of type VARCHAR to INTEGER and vice versa (i.e. from INTEGER type to VARCHAR) in Informix 4GL.

回答1:

DEFINE v VARCHAR(20)
DEFINE i INTEGER

LET v = "12345"
LET i = v
DISPLAY "i = ", i, "; v = ", v

LET i = 123456
LET v = i
DISPLAY "i = ", i, "; v = ", v

Easy, huh?

You run into problems if the string can't be converted to a number (run time errors, etc).

In essence, I4GL will automatically convert between types if it is possible, only generating an error if it is impossible. Some conversions are impossible. For example, I don't think you'd be able to convert a DECIMAL or INTEGER into an INTERVAL YEAR TO MONTH.