﻿ MID\$ Function ---------------------------------------------------------------------------- Action Returns a substring of a string. Syntax MID\$( stringexpression\$, start%, length%) Remarks The MID\$ function uses the following arguments. ----------------------------------------------------------------------------- Argument Description ---------------------------------------------------------------------------- stringexpression\$ The string expression from which the substring is extracted. This can be any string expression. start% The character position in stringexpression\$ where the Argument Description ---------------------------------------------------------------------------- stringexpression\$ where the substring starts. length% The number of characters to extract. The arguments start% and length% must be between 1 and 32,767, inclusive. If length% is omitted or if there are fewer than length% characters in the string (including the start% character), the MID\$ function returns all characters from the position start% to the end of the string. If start% is greater than the number of characters in stringexpression\$, MID\$ returns a null string. Use the LEN function to find the number of characters in stringexpression\$. See Also LEFT\$, LEN, MID\$ Statement, RIGHT\$ Example The following example converts a binary number to a decimal number. The program uses the MID\$ function to extract digits from the binary number (input as a string). INPUT "Binary number = ", Binary\$' Input binary number as string. Length = LEN(Binary\$)' Get length of string. Decimal = 0 FOR K = 1 TO Length Digit\$ = MID\$(Binary\$, K, 1) ' Get digit from string. IF Digit\$ = "0" OR Digit\$ = "1" THEN' Test for binary digit. Decimal = 2 * Decimal + VAL(Digit\$)' Convert digits to numbers. ELSE PRINT "Error--invalid binary digit. "; Digit\$ EXIT FOR END IF NEXT PRINT "Decimal number =" Decimal