c registry example
Can I delete a file extension not valid from my computer?
I exported some data from a program and stored on computer file without extension – that's what we want. When you open a file, I clicked on the program I wanted to open with, however, I forgot to disable the "Always Open With". Many of my files are stored as dates, with 25 months and my end of the month (ie, file names are 2008.01.25, etc.) Now when I try to export the system reads the files as type '25'…. a file type not valid. How do I reset the system does not recognize this file type? Data Additional file should remain generic. For example, I open Internet Explorer, Excel, Word, etc. Person B opens with Excel only, Person C wants the text, so I renewed 20080125, when the export (removal of 25 in the name) but I still have to delete the invalid file extension on my system. I guess through the registry edit …. I'm not sure.
You do not need to modify the registry. If you using Windows 2000 or Windows XP: 1. Open a folder. 2. At the top of the file, select "Tools". 3. Go to "Folder Options … "4. Select the File Types tab''5. Highlight the "25" extension and click the Delete button 6. Yes, when prompted to confirm, select''
Regular expressions allow to find patterns in strings, for example, all H1 tags in an HTML file, or all words starting with the letter "p". Although the use of regular expressions is possible in several programming languages is support for regular expressions Perl makes the language of choice for the match and the substitution pattern.
In Perl, there are three main uses filtering: matching, substitution, and translation. This article we focus on the replacement operation, which replaces an expression of the other.
Perl The Perl script below shows a typical model that can be used to process all HTML files in the folder or the current directory, ie when the Perl script and files should be treated.
<![CDATA[ 1 opendir (DIR, ".") Or die "can not opendir: $!" 2 @ = allfiles grep (/. htm $ / i, readdir DIR), 3 closedir (DIR), 4 foreach $ name (@ allfiles) ($ 5 to rename the file "$ file.bak"; 6 open (IN, "$ file ") 8 while ($ row = <in> ) (9 regular expression GOES HERE 10 (print $ line); 11) 12 close IN; 13 of about 14;) </in>]]>
Here is a description very quick script:
Lines 1 to 3: Gets all the filenames of files in the current directory and puts them in a table called @ Allfiles. (In Perl, the "@" symbol is used to identify and wide, while the "$" symbol identifies a variable.)
The lines 4 to 11: Each case is treated separately.
Lines 12 to 14: Close the script.
Line 9: This is where the expression is regular.
To run the script, you need a Perl interpreter installed on your computer. If the above script is called script1.pl then able to run it by double clicking it in, say, Windows Explorer, or open a DOS window (for example), and Perl script1.pl type "(without quotes) in the command line in the directory where the files are stored in address.
Exchange Operator
As mentioned earlier, line 9 is where Pattern Matching (alternative) intervention surgery, performed using a regular expression, leaves.
The operation Substition use the s / / / operator, and is used to change the strings. For example, you can change all occurrences of the word hello ',' a 'goodbye'. To this end, please use the following regular expression (instead of line 9 in the script above):
$ Line = ~ s / Hello / Goodbye /;
The variable "$ line" holds the string being processed, and it gets changed if the replacement is successful, ie, if the word "Hello" is, is changed to "farewell".
The '= ~' is called the comparison operator, and replacement 's' means'.
Replacement Options
The regular expression Previous changes only the first occurrence of "hello" to "goodbye" to the processing chain. For example, if we had the next segment of text, only the first "hello" be amended
I welcome anyone who knows me, and hello to all I know.
The line of text would be:
I want to say goodbye to all those who know me, and hello to everyone who knows me.
The following regular expression, however, will change all occurrences:
$ Line = ~ s / Hello / Goodbye / g;
The "G" at the end of the means of expression "global" and ensures that all occurrences of the word "any" changes.
There are several options for replacing the other, for example, "i" (i nsensitive) can be used to ignore case of letters, so that, for example, the word "hello" will be replaced independently stem and tiny used – Hello, hello, hello – would all be replaced.
Other replacement options are:
s causing the string to be treated as a single line, so that the end of the line (a backslash followed by n) are compared, and
m, causing the string to be treated as multiple lines.
Meta Characters
The meta-characters are characters that have special meaning when creating search patterns. For example, the character '|' alternation is objectivity, and allows you to specify two values that can be combined for the replacement of success. For example, the following regular expression will succeed but 'hello' or 'hello' are – both will be changed to "farewell".
$ Line = ~ s / Hello | Hi / Bye / G;
Note that if the "G" (for the world – see above) was omitted, only the first occurrence of one of the conclusions 'hello' or 'hello' would be replaced.
A couple of other characters commonly used meta are '*' and '+'. The '*' is used to compare the immediate left of the '*' key 0 or more times, while the '+' is used to match the character immediately to the left of "+" 1 or more times. These Meta tags are often used in combination with target sequences (see below).
Target sequences
Target sequences characters are given special importance of having a bar placed in front of them. For example, the backslash 'd' signifies a single digit. Therefore, comparing (and alternate) one or more digits you use the scroll bar inverted d followed by the "+".
Other sequences of metadata that must have a bar placed before them, are s (single space) t (TAB), and r (carriage return).
Shooting
Different media types can be used as part of a regular expression, For example, the use of brackets [...] can be used to create a character class. For example, substitution of the following will be true if a, b, c, or are.
$ Line = ~ s / [abc] / / g;
Note that [abc] means the same as a | b | c.
The sequence of support (…) Can be used to remember a pattern. For example, substitution of the following erase the entire contents of a file, so use with caution!
$ Line = ~ s /(.*?)// g;
The '.', '*', Y '? "Are all the characters of the target and can be used together to fit all, usually a starting point and end point, like this:
$ Line = ~ s /(.*?)/$ 1 / g;
This replacement will change all the lines at a level of two lines in an HTML file. The "$ 1" is a memory buffer is used to store the contents match the'(.*?)'. (Note: spaces in the tag names are for display purposes – to ensure that labels untreated.)
