LOCAL a,b
a = ''
b = 'A'
IF udf1(a,b)
    ? 'A包含B'
ELSE
    ? 'A不包含B'
ENDIF
FUNCTION UDF1 (a,b)
    LOCAL lFlag
    FOR i = 1 TO LENC(b)
        IF !SUBSTRC(b,i,1) $ a
            lFlag = .t.
            EXIT
        ENDIF
    NEXT
    RETURN !lFlag
ENDFUNC