String bit length?

[aliasxneo]

Does anyone know how to get the bit length of a string in PHP? Thanks.

- Josh

[Mike Tomasello]

Does anyone know how to get the bit length of a string in PHP? Thanks.

- Josh

I must admit I have no idea what you're getting at, but might strlen work?

Mike

[aliasxneo]

I'm trying to determine the amount of space a string takes up in bytes. I know how to do it in MySQL:

SELECT SUM(BIT_LENGTH(blobfieldname)) FROM DATA WHERE user_id=1

That will give me the number of bytes for "blobfieldname" where "user_id" is equal to 1.

Oh, and strlen wouldn't work because a character does not exactly represent a byte.

[Mike Tomasello]

I'm trying to determine the amount of space a string takes up in bytes. I know how to do it in MySQL:

SELECT SUM(BIT_LENGTH(blobfieldname)) FROM DATA WHERE user_id=1

That will give me the number of bytes for "blobfieldname" where "user_id" is equal to 1.

Oh, and strlen wouldn't work because a character does not exactly represent a byte.

Okay

How about this:

mb_strwidth

(PHP 4 >= 4.0.6, PHP 5)
mb_strwidth -- Return width of string
Description

int mb_strwidth ( string str [, string encoding] )

mb_strwidth() returns width of string str.
Multi-byte character usually twice of width compare to single byte character.

Table 1. Characters width
Chars..............Width
U+0000 - U+0019....0
U+0020 - U+1FFF....1
U+2000 - U+FF60....2
U+FF61 - U+FF9F....1
U+FFA0 -...........2

encoding is character encoding. If it is omitted, internal encoding is used.

Sorry if I'm being useless :D

Mike

[aliasxneo]

Okay

How about this:

Sorry if I'm being useless :D

Mike

It's okay :p But yea don't think that's it either, I don't even have the function defined:

Fatal error: Call to undefined function mb_strwidth() in C:\webpages\test.php on line 4

But after reading the PHP documentation I think that's just encoding.

[Mike Tomasello]

It's okay :p But yea don't think that's it either, I don't even have the function defined:



[/b]But after reading the PHP documentation I think that's just encoding.

If you know the 'width' of a character, then can't you determine its size in bytes from its length? For example, an ASCII character is 8-bit, so if you have a string "hello" in ASCII, is it not 40 bits wide? Maybe there are subtleties of character encoding that I have no idea about.

Mike

[aliasxneo]

If you know the 'width' of a character, then can't you determine its size in bytes from its length? For example, an ASCII character is 8-bit, so if you have a string "hello" in ASCII, is it not 40 bits wide? Maybe there are subtleties of character encoding that I have no idea about.

Mike

I'm not really sure on that, which is why I'm looking for a function to handle that for me :p