Mark of Cain

Programming Tips and Reminders

Edited: March 28th, 2011

Here will be a collection of programming tips -- for myself.  If you can benefit from them too that would be great!

This post is a reminder for me on how to do wildcard selection in jQuery.  It comes up more than you think and for some reason, I can never remember it.

<div id='pnlUsers'>div>
<div id='pnlMessages'>div>
<div id='pnlStatus'>div>

I can easily hide all the divs up by doing a wildcard selection on elements with an id starting with “pnl”, like this:



You can even narrow it to only divs like this:

How to fix the alert problem of result - object Object

 for (key in testObj){      alert ("testObj["+key +"] = "+testObj[key]);     }



for (key in e) {

//alert(key + " " + e);

if (key == "srcElement") {

for (key2 in e[key]) {

for (key3 in e[key][key2]) {

if (key3 == "id") {

alert(key3 + " " + e[key][key2]);






The following should be escaped if you are trying to match that character

\ ^ . $ | ( ) [ ]
* + ? { } ,

Special Character Definitions
\ Quote the next metacharacter
^ Match the beginning of the line
. Match any character (except newline)
$ Match the end of the line (or before newline at the end)
| Alternation
() Grouping
[] Character class
* Match 0 or more times
+ Match 1 or more times
? Match 1 or 0 times
{n} Match exactly n times
{n,} Match at least n times
{n,m} Match at least n but not more than m times
More Special Character Stuff
\t tab (HT, TAB)
\n newline (LF, NL)
\r return (CR)
\f form feed (FF)
\a alarm (bell) (BEL)
\e escape (think troff) (ESC)
\033 octal char (think of a PDP-11)
\x1B hex char
\c[ control char
\l lowercase next char (think vi)
\u uppercase next char (think vi)
\L lowercase till \E (think vi)
\U uppercase till \E (think vi)
\E end case modification (think vi)
\Q quote (disable) pattern metacharacters till \E
Even More Special Characters
\w Match a "word" character (alphanumeric plus "_")
\W Match a non-word character
\s Match a whitespace character
\S Match a non-whitespace character
\d Match a digit character
\D Match a non-digit character
\b Match a word boundary
\B Match a non-(word boundary)
\A Match only at beginning of string
\Z Match only at end of string, or before newline at the end
\z Match only at end of string
\G Match only where previous m//g left off (works only with /g)

Windows Command Line Reference

Edited: February 27th, 2015

Here is a handy reference over at Micro$oft for the windows command line:
How to slurp all images from a css file:
wget -r -P ./temp -A jpg,gif,png

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