# String

This chapter lists code examples about handling strings, including Generate a fixed-length string, Search for and replace a substring, Get part of a string, Concatenation of strings, Upper and lower-case letters identification and conversion, Remove blank spaces on both sides of a string, Format string matching, Match format strings with ' *', Get Unicode and return characters by Unicode, Split a string into a sequence, Concatenate members of a sequence into a string, Delete certain characters from a string, Check if a string consists of alphabetic and numeric characters, Compute an expression stored in a string, Use parameters to compute a string expression, and Adjuste string expression during editing.

## Generate a fixed - length string

 A 1 =fill(" ",10) "  " 2 =len(A1) 10 3 =fill("ab",10) abababababababababab

## Search for and replace a substring

 A 1 =pos("abcdef","def") Determine the position of "def" in "abcdef" 2 =pos("abcdefdef","def",5) Search from the fifth character 3 =replace("abca","a","ABC") Replace "a" with "ABC" in "abca" 4 =replace("abc'abc'","a","ABC") The substring in the single quotation marks will also be replaced 5 =replace@q("abc'abc'","a","ABC") The substring in the single quotation marks will not be replaced

## Get part of a string

 A 1 =mid("abcde",2,1) Get the second character 2 =mid("abcde",3,2) Get 2 characters from the third position 3 =mid("abcde",2) Get characters from the second position to the end 4 =left("abcdefg",3) The leftmost three characters 5 =right("abcde",2) The rightmost two characters

## Concatenation of strings

 A 1 ="ab"+"cd" abcd 2 ="3"+2 The result is 5 because the string is taken as number when computed with numbers. 3 ="ab"+1 The result is 1 because the string that can’t be converted to a number will be taken as 0.

## Upper- and lower-case letters identification and conversion

 A 1 =upper("abcdef") "ABCDEF" 2 =upper("ABCdef") "ABCDEF" 3 =lower("abcDEF") "abcdef" 4 =isupper("ABC") true 5 =islower("ABC") false 6 =islower("aBc") false 7 =isupper("Bc") false

## Remove blank spaces on both sides of a string

 A 1 =trim(" abc ") Remove spaces on both sides 2 =trim@l(" abc ") Remove the spaces on the left 3 =trim@r(" abc ") Remove the spaces on the right

## Format string matching

 A 1 =like("abc123","abc1?3") "?" is used to match a single character 2 =like("abcefg","abc*") "*" is used to match 0 or multiple characters

## Match format strings with ' * '

 A 1 =like("ab*123", "ab\*1?3") Make "*" escaped with "\" to match the character itself. 2 =like("a*bcefg","a\*bc*") true

## Get Unicode and return characters by Unicode

 A 1 =asc("a") Get the unicode of  character "a" 2 =char(68) Get the character corresponding to  code "68" 3 =asc("USA") Get the Unicode corresponding to character "U"

## Split a string into a sequence

 A 1 ="12345678" 2 =len(A1) 3 =A1.split() Split A1 into a sequence of characters 4 ="a,[b,c],d" 5 =A4.split@cp() Return a sequence which consists of three members a ,[b,c], d where the member [b,c] is a sequence 6 =A4.split@c() Return a sequence which consists of three members a ,[b,c], d where the member [b,c] is a string instead of a sequence 7 =A4.split@cb() Return a sequence which consists of four members a ,[b,c], d. The quotation marks and brackets will not be matched. 8 ="a;[b;c];d".split@p(";") Use ";" as the delimiter

## Concatenate members of a sequence into a string

 A 1 =[1,"abc,def",[2,4],"{7,8}"] 2 =A1.concat@cq() Use "," as the delimiter to concatenate members , in which strings will be quoted 3 =A1.concat() String members don't need to be quoted and separated when being concatenated 4 =A1.concat("&") Use "&" as the delimiter

## Delete certain characters from a string

 A 1 abcda123efag 2 =replace(A1,"123","") Remove "123" 3 =replace(A1,"a","") remove "a"

## Check if a string consists of alphabetic and numeric characters

 A 1 2345\$#dfAgsdf23* 2 =len(A1) 16 3 =A1.split() Split A1 into a sequence of characters 4 =A3.count(!isdigit(~) && !isalpha(~))==0 Check if it is a alphanumeric string

## Compute an expression stored in a string

 A 1 =eval("1+5") Compute 1 + 5 2 =eval(\$[A1+2]) Compute A1 + 2

## Use parameter s to comput e a string expression

 A 1 =eval("?+5",3) Equivalent to "3 + 5" 2 =eval("(?1+1)/?2",3,4) Equivalent to "(3 + 1)/4"

## Adjust string e xpression s during editing

 A 1 =\$[B1+4] Strings written in the format of \$[] will adjust themselves during editing