true if

PHP array comparison function. If an intersection exists, true is returned. otherwise, false is returned. Copy the code as follows :? Php $ array1array (a, B, c, d); $ array2array (a, c); $ array3array_intersect ($ array1, $ array2); if ($ array3)

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Tested: {code...} reply content: See the PHP document: empty-check whether a variable is empty Obviously, obj is not empty ~ Test: Print_r ($ obj ); Game Object () Empty or non-empty are defined. don't guess ...... The object has been

javascript| function /* --------------function Retrieval-------------- Trim function:                          trim () LTrim () RTrim () Verify that the string is empty:                 Checkisnotempty (str) Verify that the string is an integral

Conditional expression ("CONDITIONAL EXPRESSIONS") Conditional expressions are used in [composite commands and built-in command test and [to test file properties for string and arithmetic comparisons.] An expression is constructed using the

Test Condition Expression Description File symbols: [Root@lamp test]# Help testtest:test [expr]Evaluate conditional expression.Exits with a status of 0 (True) or 1 (false) depending onThe evaluation of EXPR.  Expressions May is unary or binary.

1. Create and run Shell programsWhat is a shell program? Simply put, a shell program is a program that contains several rows.Shell or Linux Command file.Like programming in advanced languages, writing a shell program requires a text editor, such as

1. DOM functions A, Domdocument->load () Role: Loading an XML file Usage: domdocument->load (string filename) Parameters: Filename,xml file; Returns: TRUE if successful, or FALSE if unsuccessful. B, Domdocument->loadxml () Role: Loading XML

The way to compare two strings for equality is:If ["$test" x = "Test" x]; ThenHere are a few key points:1 using a single equals sign2 Note that there is a space on each side of the equal sign: This is the UNIX shell requirement3 Notice the last X of

Http://www.3800hk.com/Article/ OS /Linux/bckflu/2005-08-06/Article_37229_2.html Code :-------------------------------------------------------------------------------- 1. Create and run Shell programsWhat is a shell program? Simply put, a shell

1. DOM functionsA, Domdocument-Role: Loading an XML fileUsage: domdocument-Parameters: Filename,xml file;Returns: TRUE if successful, or FALSE if unsuccessful.B, Domdocument-Role: Loading XML codeUsage: Domdocument-Parameters: source XML

1. DOM function A, Domdocument->load ()Function: Load XML fileUsage: domdocument->load (string filename)Parameters: Filename,xml file;Return: Returns TRUE if successful and FALSE if failed. B, Domdocument->loadxml ()function: Load XML codeUsage:

$ () and "(anti-quote ) are used to do command substitution. Next, let's see ${} ... It's actually used for variable substitution. Shell if interpretation statements are common:[Front and rear spaces] Front Space[-D file] True if file exists and

Objective:No matter what programming language is inseparable from conditional judgment. The shell is no exception.Copy CodeThe code is as follows:If List ThenDo something hereElif List ThenDo another thing hereElseDo something else hereFiEX1:Copy

Shell condition judgmentIf List ThenDo something hereElif List ThenDo another thing hereElseDo something else hereFiEX1:#!/bin/shSystem= ' uname-s ' #获取操作系统类型, I'm local Linuxif [$SYSTEM = "Linux"]; Then #如果是linux的话打印linux字符串echo "Linux"elif

1. string Judgments STR1 = str2 True when two strings have the same content, length Str1! = str2 True when strings str1 and str2 are unequal -N str1 True when the length of a string is

Source: http://www.diybl.com/course/6_system/linux/Linuxjs/20081117/151774.html For more information, see the original article.   -B file: if the file exists and is a special block file, it is true.-C file: if the file exists and is a special

The basis of each conditional statement is to determine what is true and what is false. Knowing how it works will determine whether you're writing a quality-generic script or a script that you'll be proud of. The ability of a Shell script is often

The basis of each conditional statement is to determine what is true and what is false. Knowing how it works will determine whether you're writing a quality-generic script or a script that you'll be proud of. The ability of a Shell script is often

In shell, if is used to compare whether two strings are equal: www.2cto. comif [& quot; $ test & quot; x & quot; test & quot; x]; then has the following key points: 1. use a single equal sign 2 to notice that there is a space on both sides of the