แม่แบบ:Str left
การใช้งาน
[แก้]{{Str left|<string>|<count>}}
Gives the resultant <count> of characters creating a substring of characters from the start of the trimmed string (i.e. the substring returned will have length <count>, exclusive of leading whitespace characters, which are trimmed first before <count> is invoked).
If <count> is invalid, empty or zero, an empty string is returned. If undefined, it defaults to 1.
ข้อจำกัด
[แก้]- Length to 500: The maximum substring stops at 500 long, yet gives no error message. Only 500 characters can be extracted even if the <string> is longer.
- Inexpensive (uses no other templates).
ตัวอย่าง
[แก้]{{ Str left | Lorem ipsum dolor sit amet | 10 }}→ Lorem ipsu{{Str left| Lorem ipsum dolor sit amet | 4 }}→ Lore, (note leading spaces trimmed!){{ Str left | Lorem ipsum dolor sit amet | 1 }}→ L{{ Str left | Lorem ipsum dolor sit amet | 0 }}→{{ Str left | Lorem ipsum dolor sit amet | }}→{{ Str left | Lorem ipsum dolor sit amet }}→ L{{ Str left | Lorem ipsum dolor sit amet | 40 }}→ Lorem ipsum dolor sit ametLorem ipsum do{{ Str left | àçé | 2 }}→ àç- This example is demonstrating the safety of this template with the UTF-8 encoding (this should work now) :
ตัวอย่างข้อจำกัด
[แก้]All the limitations of use for this template and shown below are caused by the current implementation of the {{padleft:}} parser function used in this template, which does not filter its third parameter containing the characters used for padding a string to the specified length (it currently counts incorrectly the characters to extract from the padding string, and incorrectly measures its effective length; in addition this parameter is limited to 500 bytes).
The following examples are demonstrating that this template does not interpret character entity references as the character they represent. It treats them as multiple characters and can leave them truncated.
{{ Str left | a c | 3 }}→ a&n- The output "a c" may have been intended, but the named character entity was truncated, leaving no length available for the final "c".
{{ Str left | aBc | 3 }}→ a&#- This should display "abc", but the named character entity was truncated, leaving no length available for the final "c".
{{ Str left | a c | 3 }}→ a c- The result is correct, as expected.
{{ Str left | a c | 3 }}→ a&#- This last example should be equivalent to the previous one, but it is not.
This template will erase nowiki tags without counting their length:
{{ Str left | a<nowiki/>bcd | 3 }}→ abc- Returns three characters as expected
{{ Str left | a<nowiki>E</nowiki>bcd | 3 }}→ abc- Returns three characters, but not aEb as might have been expected.
{{ Str left | a<nowiki/>bc | 10 }}→ abcabcabca- Returns 10 characters as expected.
HTML comments, and the "noinclude", "includeonly" and "onlyinclude" wiki markup tags are also ignored, because they are preprocessed in template parameters, before including it and substituting parameters:
{{ Str left | a<noinclude/>bc | 3 }}→ abc{{ Str left | a<!-- comment -->bc | 3 }}→ abc
Note also that the specified length will cause the input string to be padded by repeating it, if this length is larger than the input string length:
{{ Str left | Abc. | 10 }}→ Abc.Abc.Ab
ข้อมูลแม่แบบ
[แก้]ข้อมูลแม่แบบสำหรับ Str left
A template to give the <count> substring of characters from the start of the trimmed string
| พารามิเตอร์ | คำอธิบาย | ชนิด | สถานะ | |
|---|---|---|---|---|
| String | 1 | The string to be trimmed and counted | สตริง | จำเป็น |
| Count | 2 | Gives the <count> substring of characters from the start of the trimmed string | จำนวน | จำเป็น |
ดูเพิ่ม
[แก้]- Bugzilla:22555 (historical; need for correcting padleft/padright functions and to provide better string-handling parser functions)