Computer Programming Concepts and Visual Basic David I. Schneider

60 Computer Programming Concepts and Visual Basic
EXAMPLE 4
The following program shows how Int is used to carry out long division. When the integer m is divided
into the integer n with long division, the result is a quotient and a remainder. See Figure 2-29.
FIGURE 2-29 Long Division
Private Sub cmdDivide_Click()
Dim divisor As Single, dividend As Single
Dim quotient As Single, remainder As Single
‘Long division
picResult.Cls
divisor = Val(txtDivisor.Text)
dividend = Val(txtDividend.Text)
quotient = Int(dividend / divisor)
remainder = dividend - quotient * divisor
picResult.Print “The quotient is”; quotient
picResult.Print “The remainder is”; remainder
End Sub
[Run, type 14 and 256 into the text boxes, and then click the command button.]
■ STRING FUNCTIONS: LEFT, MID, RIGHT, UCASE,TRIM
The functions Left, Mid, and Right are used to extract characters from the left end, middle, and
right end of a string. Suppose str is a string and m and n are positive integers. Then Left(str,
n) is the string consisting of the first n characters of str and Right(str, n) is the string consisting
of the last n characters of str. Mid(str, m, n) is the string consisting of n characters of str,
beginning with the mth character. UCase(str) is the string str with all of its lowercase letters
capitalized. Trim(str) is the string str with all leading and trailing spaces removed. Some examples
are as follows:
Left(“fanatic”, 3) is “fan”. Right(“fanatic”, 3) is “tic”.
Left(“12/15/99”, 2) is ”12”. Right(“12/15/99”, 2) is ”99”.
Mid(“fanatic”, 5, 1) is “t”. Mid(“12/15/99”, 4, 2) is ”15”.
UCase(“Disk”) is “DISK”. UCase(“12three”) is “12THREE”.
Trim(“ 1 2 ”) is “1 2”. Trim(”-12 “) is ”-12”.
The strings produced by Left, Mid, and Right are referred to as substrings of the strings
from which they were formed. For instance, “fan” and “t” are substrings of “fanatic”. The
substring “fan” is said to begin at position 1 of “fanatic” and the substring “t” is said to begin
at position 5.