Left (Function)

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String management functions

Differences between GO mode and runtime

Constants for managing character strings

Functions for managing character strings

HTMLToRTF

HTMLToText

Handling Unicode in character strings

Handling character strings

MatchRegularExpression

NumToFinancialWritingChinese

Serialization constants

SystemIntegerToInteger

Left and UNICODE
Differences between GO mode and runtime

WINDEV

WEBDEV

WINDEV Mobile

Others

See also

Left (Function)

In french: Gauche

Extracts the left part (i.e., the first characters) from a string or buffer.

In this version, the left part of a buffer cannot be extracted.

Versions 15 and later

This function is now available for Android applications.

New in version 15

This function is now available for Android applications.

Versions 17 and later

This function is now available for iPhone/iPad applications.

New in version 17

This function is now available for iPhone/iPad applications.

Versions 18 and later

This function is now available in Android Widget mode.

This function is now available in Windows Store apps mode.

New in version 18

This function is now available in Android Widget mode.

This function is now available in Windows Store apps mode.

This function is now available in Android Widget mode.

This function is now available in Windows Store apps mode.

Versions 21 and later

This function is now available in Apple Watch mode.

This function is now available in Universal Windows 10 App mode.

New in version 21

This function is now available in Apple Watch mode.

This function is now available in Universal Windows 10 App mode.

This function is now available in Apple Watch mode.

This function is now available in Universal Windows 10 App mode.

Example

Left("The cuckoo", 6) // Returns "The cu"
Left("ABC", 50) // Returns "ABC"
Left("AZELMA ") // Returns "AZELMA"

MyString is string = "Developing is child's play"
Left(MyString, 10) // Returns "Developing"

// Extract bytes
MyBuffer is Buffer = "Developing is child's play"
Left(MyBuffer, 10) // Returns "Developing"

Syntax

Extracting the left part of a character string Hide the details

<Result> = Left(<Initial string> [, <Length>])

<Result>: Character string

Left part of <Initial string>. Corresponds to <Initial string> if <Length> is greater than the length of <Initial string>.
EOT if <Length> is negative. A WLanguage error occurs (non-fatal error). To get the details of the error, use ErrorInfo.

<Initial string>: Character string (with quotes)

Character string from which the left part will be extracted. This string is not modified.

<Length>: Optional integer

Number of characters to extract. If this parameter is not specified, <Result> corresponds to <Initial string> without trailing spaces.

Extracting the left part of a buffer Hide the details

<Result> = Left(<Initial buffer> [, <Size>])

<Result>: Character string

Left part of <Initial buffer>. Corresponds to <Initial buffer> if <Size> is greater than the size of <Initial buffer>.
EOT if <Size> is negative. A WLanguage error occurs (non-fatal error). To find out the error details, use ErrorInfo.
Invalid buffer if <Initial buffer> contains a UNICODE string.
Invalid buffer if <Initial buffer> contains an ANSI string.

<Initial buffer>: Buffer

Buffer from which the left part will be extracted. This buffer is not modified.

<Size>: Optional integer

Number of bytes to extract. If this parameter is not specified, <Result> corresponds to <Initial buffer> without trailing spaces.
In UNICODE, each character occupies two bytes of memory. Therefore, the number of bytes is twice the number of characters.

Remarks

Left and UNICODE

If the string passed as a parameter is in ANSI format, the result will be in ANSI format.

If the string passed as a parameter is in UNICODE format, the result will be in UNICODE format.

Reminder: In UNICODE, each character occupies two bytes of memory. Therefore, the memory footprint of a UNICODE string is twice the number of characters actually contained in the string.

The fist character in the string is at index 1.

Remark: If the result on an ANSI string is assigned to a UNICODE string (and conversely), the conversion will be implicitly performed.

See Managing UNICODE for more details.

Differences between GO mode and runtime

In GO mode (simulation on the development computer), when extracting the left part of a buffer (syntax 2), <Size> corresponds to the number of characters to extract and not the number of bytes.

For example, when the following code is executed:

MyBuffer is Buffer = "WINDEV is tremendous"
Left(MyBuffer, 6)

The result is as follows:

in GO mode, this code returns "WINDEV".
at runtime, this code returns "Win".

The differences between GO mode (simulator) and runtime are presented in Differences between GO mode and runtime.

Component : wd260vm.dll