TDes8 Class Reference

Expand all characters from 8 to 16 bits

The length of descriptor increased by 2 (length *= 2).

Fills the descriptor's data area with the specified character, replacing any existing data.

The descriptor is filled from the beginning up to its current length. The descriptor's length does not change. It is not filled to its maximum length.

Fills the descriptor's data area with the specified character, replacing any existing data.

The descriptor is filled with the specified number of characters. and its length is changed to reflect this.

Fills the descriptor's data area with binary zeroes, i.e. 0x00, replacing any existing data.

The descriptor is filled from the beginning up to its current length. The descriptor's length does not change. It is not filled to its maximum length.

Fills the descriptor's data area with binary zeroes, i.e. 0x00, replacing any existing data, and changes its length.

The descriptor is filled with the specified number of binary zeroes. The descriptor's length is changed to reflect this.

Performs folding on the content of this descriptor.

Note that folding is locale-independent behaviour. It is also important to note that there can be no guarantee that folding is in any way culturally appropriate, and should not be used when dealing with strings in natural language.

Formats and copies text into this descriptor, replacing any existing data.

The length of this descriptor is set to reflect the new data.

The function takes a format string and a variable number of arguments. The format string contains literal text embedded with directives for converting the trailing list of arguments into text.

The embedded directives are character sequences prefixed with the '' character. The literal text is simply copied into this descriptor unaltered while the '' directives are used to convert successive arguments from the trailing list.

The resulting stream of literal text and converted arguments is copied into this descriptor.

The syntax of the embedded directives follows one of four general patterns.

Note that formatting of single numerical values can be achieved more conveniently using the Num() and NumUC() member functions of this class.

The full description of the syntax of a format string cannot be included here. For full details, navigate to the Symbian OS guide, and follow the hierarchy of links:

Symbian OS Guide
	Base
		Using  User Library (E32)
			Buffers and Strings
				Using Descriptors
					How to Use Descriptors
						Format string syntax

See also: TDes8::Num() TDes8::NumUC()

Formats and copies text into this descriptor, replacing any existing data.

The length of this descriptor is set to reflect the new data.

The behaviour of this function is the same as Format(). In practice, it is better and easier to use Format(), passing a variable number of arguments as required by the format string.

See also: TDes8::Format() VA_LIST

Inserts data into this descriptor.

The length of this descriptor is changed to reflect the extra data.

Copies data into this descriptor and justifies it, replacing any existing data.

The length of this descriptor is set to reflect the new data.

The target area is considered to be an area of specified width positioned at the beginning of this descriptor's data area. Source data is copied into, and aligned within this target area according to the specified alignment instruction.

If the length of the target area is larger than the length of the source, then spare space within the target area is padded with the fill character.

Extracts the leftmost part of the data.

The function does not cut or remove any data but constructs a modifiable pointer descriptor to represent the leftmost part of the data.

Converts the content of this descriptor to lower case.

Conversion is implemented as appropriate to the current locale.

Gets the maximum length of the descriptor.

This is the upper limit for the number of 8-bit values or data items that the descriptor can represent.

Gets the maximum size of the descriptor.

This is the upper limit for the number of bytes which the data represented by the descriptor can occupy.

Extracts a portion of the data.

The function does not cut or remove any data but constructs a modifiable pointer descriptor to represent the defined portion.

The portion is identified by its starting position and by the length of the remainder of the data starting from the specified position.

Extracts a portion of the data.

The function does not cut or remove any data but constructs a modifiable pointer descriptor to represent the defined portion.

The portion is identified by its starting position and by its length.

Converts the 64-bit signed integer into a decimal character representation and copies the conversion into this descriptor, replacing any existing data.

The length of this descriptor is set to reflect the new data.

If the integer is negative, the character representation is prefixed by a minus sign.

Converts the specified 64-bit unsigned integer into a character representation based on the specified number system and copies the conversion into this descriptor, replacing any existing data.

The length of this descriptor is set to reflect the new data.

When a hexadecimal conversion is specified, hexadecimal characters are in lower case.

Converts the specified floating point number into a character representation and copies the conversion into this descriptor, replacing any existing data.

The length of this descriptor is set to reflect the new data.

The character representation of the real number is dictated by the specified format.

Note that the function leaves if the iType data member of the specified TRealFormat object has both an invalid character representation format (i.e. the format type) and invalid format flags.

1.KErrArgument - the supplied floating point number is not a valid number. The three characters NaN are appended to this descriptor.

2.KErrOverflow - the number is too large to represent. 2.1 For positive overflow, the three characters Inf are appended to this descriptor. 2.2 For negative overflow, the four characters -Inf are appended to this descriptor.

3.KErrUnderflow - the number is too small to represent. 3.1 For positive underflow, the three characters Inf are appended to this descriptor. 3.2 For negative underflow, the four characters -Inf are appended to this descriptor.

4.KErrGeneral - the conversion cannot be completed. There are a number of possible reasons for this, but the two most common are: 4.1 the maximum number of characters necessary to represent the number, as defined in the TRealFormat object, is greater than the maximum length of this descriptor 4.2 the character representation format (i.e. the format type), as defined in the TRealFormat object is not recognised.

See also: TRealFormat::iType

Converts the specified unsigned integer into a fixed width character representation based on the specified number system and copies the conversion into this descriptor, replacing any existing data.

The length of this descriptor is set to reflect the new data.

The function generates the exact number of specified characters, either padding to the left with character zeroes or discarding low order characters as necessary.

When a hexadecimal conversion is specified, hexadecimal characters are in lower case.

This function is equivalent to using Format() with parameters which specify:

1. a fixed length target field

2. padding with zero characters, for example "%08x".

When this is the case, always use NumFixedWidth() in preference to Format() as it is more efficient.

See also: TDes8::Format()

Converts the specified unsigned integer into a fixed width character representation based on the specified number system and copies the conversion into this descriptor, replacing any existing data.

The length of this descriptor is set to reflect the new data.

The function generates the exact number of specified characters, either padding to the left with character zeroes or discarding low order characters as necessary.

When a hexadecimal conversion is specified, hexadecimal characters are in upper case.

This function is equivalent to using Format() with parameters which specify:

1. a fixed length target field

2. padding with zero characters, for example "%08x".

When this is the case, always use NumFixedWidthUC() in preference to Format() as it is more efficient.

See also: TDes8::Format()

Converts the specified 64-bit unsigned integer into a character representation based on the specified number system and copies the conversion into this descriptor, replacing any existing data.

The length of this descriptor is set to reflect the new data.

When a hexadecimal conversion is specified, hexadecimal characters are in upper case.

Appends a zero terminator onto the end of this descriptor's data and returns a pointer to the data.

The length of the descriptor is not changed. It must, however, be strictly less than the descriptor's maximum length. This condition guarantees that there is sufficient space for the zero terminator.

Copies data with repetition into this descriptor, from a memory location specified by pointer, replacing any existing data.

Copying proceeds until this descriptor is filled up to its current length. If it cannot contain a whole number of copies of the source data, then the last copy is truncated.

Copies data with repetition into this descriptor, from another descriptor, replacing any existing data.

Copying proceeds until this descriptor is filled up to its current length. If it cannot contain a whole number of copies of the source data, then the last copy is truncated.

Replaces data in this descriptor.

The specified length can be different to the length of the replacement data. The length of this descriptor changes to reflect the change of data.

Extracts the rightmost part of the data.

The function does not cut or remove any data but constructs a modifiable pointer descriptor to represent the rightmost part of the data.

Sets the length of the data represented by the descriptor to the specified value.

Sets the length of the data to the maximum length of the descriptor.

Swaps the data represented by this descriptor with the data represented by the specified descriptor.

The lengths of both descriptors are swapped to reflect the change.

Note that each descriptor must be capable of accommodating the contents of the other descriptor.

Deletes leading and trailing whitespace characters from the descriptor's data.

The length of the descriptor is reduced to reflect the loss of the whitespace characters.

See also: TDes8::TrimLeft() TDes8::TrimRight()

Deletes leading and trailing whitespace characters from the descriptor's data and replaces each contiguous set of whitespace characters within the data by one whitespace character.

The length of the descriptor is reduced to reflect the loss of the whitespace characters.

See also: TDes8::Trim()

Deletes leading whitespace characters from the descriptor's data.

All whitespace characters up to, but not including the first non-whitespace character, are deleted.

The length of the descriptor is reduced to reflect the loss of the whitespace characters.

Deletes trailing whitespace characters from the descriptor's data.

The process starts on the right hand side of the descriptor's data and proceeds to the left.

All whitespace characters up to, but not including the first non-whitespace character, are deleted.

The length of the descriptor is reduced to reflect the loss of the whitespace characters.

Converts the content of this descriptor to upper case.

Conversion is implemented as appropriate to the current locale.