位元組 漢字判斷

XE7

TMbcsByteType : unsigned char { mbSingleByte, mbLeadByte, mbTrailByte };

System.UnicodeString.IsLeadSurrogate

bool IsLeadSurrogate(int index)

Tests whether the element is a lead surrogate.

IsLeadSurrogate returns true if the indexed element is a lead surrogate and false otherwise. Note that index is an element index into the string, not a character or byte index. 

System.UnicodeString.IsTrailSurrogate

Tests whether the element is a trail surrogate.

IsTrailSurrogate returns True if the indexed element is a trail surrogate and False, otherwise. Note that index is an element index into the string, not a character or byte index. 

IsLeadByte

IsTrailByte

Returns true if the specified byte is a lead byte.

bool __fastcall IsLeadByte(int index) const;

Description

IsLeadByte returns true if the byte indicated by index (counting from 0) is the lead byte in a multi-byte character. If the byte is a trailing byte, or not part of a multi-byte character, IsLeadByte returns false.

Returns true if the specified byte is of type mbTrailByte.

bool __fastcall IsTrailByte(int index) const;

IsTrailByte returns true if the byte indicated by index (counting from 0) is the trailing byte in a multi-byte character. If the byte is a lead byte, or not part of a multi-byte character, IsTrailByte returns false.

System.SysUtils.TMbcsByteType

TMbcsByteType represents the use of a single byte in a string that uses a multi-byte character set (MBCS).

TMbcsByteType represents the possible return values of the ByteType and StrByteType functions. Possible values are as follows. 

mbSingleByte

The char is used to represent an entire character in the string. The value of Char cannot be included in the LeadBytes set.

mbLeadByte

The char is used to represent the first byte of a multi-byte character. The value of Char must be included in the LeadBytes set.

mbTrailByte

The char is used to represent one of the trailing bytes in a multi-byte character. There are no a priori restrictions on the value of char.

判斷是否數字數值

IsDigit

判斷是否