Pravin1389: moved PHP-and-MySQL/C4/PHP-String-Functions-(Part 2)/English to PHP-and-MySQL/C4/PHP-String-Functions-Part-2/English

2012-12-01T15:40:35Z

moved PHP-and-MySQL/C4/PHP-String-Functions-(Part 2)/English to PHP-and-MySQL/C4/PHP-String-Functions-Part-2/English

Chandrika: Created page with '{|Border=1 !Time !Narration |- |0:00 |Ok back to the second part of the String Functions tutorial. |- |0:03 |I'm going to go through the rest of the functions starting from Strin…'

2012-11-29T07:02:04Z

Created page with '{|Border=1 !Time !Narration |- |0:00 |Ok back to the second part of the String Functions tutorial. |- |0:03 |I'm going to go through the rest of the functions starting from Strin…'

New page

{|Border=1
!Time
!Narration
|-
|0:00
|Ok back to the second part of the String Functions tutorial.
|-
|0:03
|I'm going to go through the rest of the functions starting from String Reverse.
|-
|0:08
|String reverse probably to make sense is s-t-r-rev.
|-
|0:11
|So what strvev does is it reverses the contents of a string.
|-
|0:20
|So if I were to say 'Hello' and I were to reverse that, it would be "o-l-l-e-H".
|-
|0:30
|And it can be useful in some circumstances although you usually wouldn't use this.
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|0:36
|But you could use this function if you want to specifically reverse a string.
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|0:41
|I think its a useful and fun function to use.
|-
|0:45
|Ok - the next set of functions I have grouped together are these: str to lower and str to upper.
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|0:54
|This basically means string to lower case and string to upper case.
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|0:58
|So if we have our string that equals 'HELLO', I can say echo str to lower and show the value of the string in there.
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|1:12
|The 'HELLO' in capitals will now become lowercase.
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|1:15
|Something similar would happen if I were to say this is 'hello' in smallcase
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|1:21
|And I could say str to upper and that would give me my uppercase version of the string.
|-
|1:31
|Now one applicable use of this is when you have user-registration.
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|1:35
|If you have a website on which users have to register, you should usually always store the user name as a lower string.
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|1:49
|The reason is that if I submit a user name - lets get rid of this...
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|1:55
|Some people actually do this - Lets have a variable user name which equals say 'ALEX'.
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|2:01
|And I'll put in these also - uppercase and smallcase alphabets.
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|2:07
|Some people use names like this to make the name look funky and its perfectly okay.
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|2:13
|But if the name is stored as this and you think - well did i start with a small a?
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|2:19
|Then I have another pattern for username now.
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|2:23
|So what you can do is say stored user name equals to str to lower of the username.
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|2:29
|So this would be the stored username in the database
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|2:33
|Now when they go to login and type in their username in this combination, what we would do is we would convert their typed-in login username to lower case and compare it to the lower case store version of the username.
|-
|2:48
|So we are taking this and storing a lowercase value inside the database and we are comparing it to a typed-in value which has also been converted to lower case
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|2:58
|Hence we can't go wrong and users are not going to forget their user-names.
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|3:07
|You could do the same with passwords.
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|3:14
|Ok lets go to the next one.
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|3:22
|Sub-string count. This would basically count the no. of sub-strings matching to a particular value inside a string.
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|3:31
|So here I'll type search equals "My name is alex. What is your name?"
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|3:37
|So this is our string.
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|3:41
|Now if I say we need to echo out the sub-string count...
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|3:49
|and obviously this stands for sub-string-count, what we want to do is, we want to search our 'search' string...
|-
|4:01
|and we will specify a string to search for. Now this will return an integer if we put this in a variable called result.
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|4:12
|That's because you can't find any instance of a word which will appear say for 1.2 times.
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|4:20
|Also the variable result will not return 2 as t-w-o. It will only return 2 as an integer.
|-
|4:30
|So this is quite useful if we are using substring count to search for, lets say, 'alex'.
|-
|4:36
|And then it will echo out on its own.
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|4:39
|And if you look through here, you will see there is only one instance of 'alex'
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|4:44
|So refresh that - and we should get the number 1.
|-
|4:46
|Now if we were to search for 'name' - there's 1 instance of 'name' here and another instance of 'name' here
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|4:52
|So when we refresh, we should get the value 2.
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|4:55
|Now there are optional parameters for this, which are 'where to start from in a string' and 'where to end in a string'.
|-
|5:02
|Lets try this out.
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|5:05
|So lets say I want to search from after name, ok?
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|5:11
|So this is 0 1 2 3 4 5 6.
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|5:14
|So I say search name from 7 onwards.
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|5:19
|So search name from 7 and it will search in this blue area that I have highlighted here.
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|5:25
|It will only return 1 in the result.
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|5:28
|So you can specify whereabouts in the string.
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|5:30
|I think you can specify upto where.
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|5:33
|So this is 7... 8 9 10 11 12 13 14 15 16.
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|5:43
|7 to 17. Lets check if this works.
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|5:46
|It shows zero. So from 7 to 17 - which is from about here to here - we find zero instances of 'name'.
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|5:55
|However if we search for 'alex', we will find 1 instance of it.
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|6:01
|Ok - so that's the substring count function.
|-
|6:07
|And now substring replace is similar.
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|6:12
|Its not the same function but it includes an added bonus where you can replace your string.
|-
|6:18
|So the replace tags are - My name is alex and I've added the full-stop on purpose.
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|6:28
|Our result is equal to substring replace.
|-
|6:33
|What do I want to replace in? I want to replace in the variable replace.
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|6:41
|And I want to replace 'alex' with 'billy'.
|-
|6:48
|And this will be from - let me count 0 1 2 3 4 5 7 8 9 10 11 so from 11 until...
|-
|7:01
|Its 11 - 0 1 2 3 4 5 6 7 8 9 10 11 - from 11 to 14.
|-
|7:14
|So that should replace 'alex' with 'billy'.
|-
|7:19
|Replace and refresh.
|-
|7:21
|Oh! We didn't echo out result.
|-
|7:23
|Lets echo out result and we can refresh this.
|-
|7:26
|And it should return my name is billy.
|-
|7:30
|This should be 12 and this 15, I think.
|-
|7:34
|Or in fact no - it should be 10 and 14.
|-
|7:38
|No, not quite right.... We are missing the full-stop.
|-
|7:43
|........ so lets go for 11 and 14.
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|7:49
|Still missing the full stop and I cant think why.
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|7:52
|aah! well you get the picture
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|7:55
|Basically you can replace anything in the string with the starting value and the ending value
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|7:59
|It will leave it up to you to count through.
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|8:04
|I'm very tired so I am not able to count.
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|8:09
|So what we are doing here is we are replacing a particular string with a particular value
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|8:14
|And here's your starting value and here's your finishing value.
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|8:17
|That's all in this tutorial.
|-
|8:19
|There are many more string functions and I suggest you to search, may be, on 'google'.
|-
|8:24
|Search for 'php string functions' and you'll find a lot of interesting functions.
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|8:28
|If you are looking to do a particular thing there's probably a function available for it.
|-
|8:33
|Thanks for watching! This is Osama Butt dubbing for the Spoken Tutorial Project.

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PHP-and-MySQL/C4/PHP-String-Functions-Part-2/English - Revision history

Pravin1389: moved PHP-and-MySQL/C4/PHP-String-Functions-(Part 2)/English to PHP-and-MySQL/C4/PHP-String-Functions-Part-2/English

Chandrika: Created page with '{|Border=1 !Time !Narration |- |0:00 |Ok back to the second part of the String Functions tutorial. |- |0:03 |I'm going to go through the rest of the functions starting from Strin…'