两个'表示一个'A character string, also called a string literal or string constant, consists of a quoted string, a control string, or a combination of quoted and control strings. Separators can occur only within quoted strings. A quoted string is a sequence of up to 255 characters from the extended ASCII character set, written on one line and enclosed by apostrophes. A quoted string with nothing between the apostrophes is a null string. Two sequential apostrophes in a quoted string denote a single character, namely an apostrophe. For example,'BORLAND' { BORLAND }'You''ll see' { You'll see } '''' { ' } '' { null string } ' ' { a space }A control string is a sequence of one or more control characters, each of which consists of the # symbol followed by an unsigned integer constant from 0 to 255 (decimal or hexadecimal) and denotes the corresponding ASCII character. The control string#89#111#117is equivalent to the quoted string'You'You can combine quoted strings with control strings to form larger character strings. For example, you could use'Line 1'#13#10'Line 2'to put a carriage-return杔ine-feed between 揕ine 1?and 揕ine 2? However, you cannot concatenate two quoted strings in this way, since a pair of sequential apostrophes is interpreted as a single character. (To concatenate quoted strings, use the + operator or simply combine them into a single quoted string.) A character string抯 length is the number of characters in the string. A character string of any length is compatible with any string type and with the PChar type. A character string of length 1 is compatible with any character type, and, when extended syntax is enabled ( {$X+}), a nonempty character string of length n is compatible with zero-based arrays and packed arrays of n characters. For more information about string types, see
a quoted string, a control string, or a combination of quoted and control strings. Separators can occur only within quoted strings.
A quoted string is a sequence of up to 255 characters from the extended ASCII character set, written on one line and enclosed by apostrophes. A quoted string with nothing between the apostrophes is a null string. Two sequential apostrophes in a quoted string denote a single character, namely an apostrophe. For example,'BORLAND' { BORLAND }'You''ll see' { You'll see }
'''' { ' }
'' { null string }
' ' { a space }A control string is a sequence of one or more control characters, each of which consists of the # symbol followed by an unsigned integer constant from 0 to 255 (decimal or hexadecimal) and denotes the corresponding ASCII character. The control string#89#111#117is equivalent to the quoted string'You'You can combine quoted strings with control strings to form larger character strings. For example, you could use'Line 1'#13#10'Line 2'to put a carriage-return杔ine-feed between 揕ine 1?and 揕ine 2? However, you cannot concatenate two quoted strings in this way, since a pair of sequential apostrophes is interpreted as a single character. (To concatenate quoted strings, use the + operator or simply combine them into a single quoted string.)
A character string抯 length is the number of characters in the string. A character string of any length is compatible with any string type and with the PChar type. A character string of length 1 is compatible with any character type, and, when extended syntax is enabled (
{$X+}), a nonempty character string of length n is compatible with zero-based arrays and packed arrays of n characters. For more information about string types, see
name是字符型的，必须加'，NAME=‘123’
支持