PHP MySQL - Stilson.net

www.it-ebooks.infoCHAPTER 9 • STRINGS AND REGULAR EXPRESSIONSBecause the provided username is not all lowercase, ereg() will not return FALSE (instead returningthe length of the matched string, which PHP will treat as TRUE), causing the error message to output.The optional input parameter regs contains an array of all matched expressions that are grouped byparentheses in the regular expression. Making use of this array, you could segment a URL into severalpieces, as shown here:echo $regs[0];echo "";echo $regs[1];echo "";echo $regs[2];echo "";echo $regs[3];// outputs the entire string "http://www.apress.com"// outputs "http://www"// outputs "apress"// outputs "com"This returns the following:http://www.apress.comhttp://wwwapresscomPerforming a Case-Insensitive SearchThe eregi() function searches a string for a defined pattern in a case-insensitive fashion. Its prototypefollows:int eregi(string pattern, string string, [array regs])This function can be useful when checking the validity of strings, such as passwords. This concept isillustrated in the following example:195