How to check if a string is in an array? How to use the Bash ternary operator? How to negate an if condition in a Bash if statement? (if not command or if not equal) How to use the BASH_REMATCH variable with the Regular Expression Operator =~?
[zexcon@fedora ~]$ ./learnToScript.sh numberTwelve variable is equal to 12 你所看到的是if语句的第一行,它在检查变量的值是否真的等于12。如果是的话,语句就会停止,并发出numberTwelve is equal to 12的回显,然后在fi之后继续执行你的脚本。如果变量大于12的话,就会执行elif语句,并在fi之后继续执行。当...
Bash, short for "Bourne Again SHell," is a powerful scripting language used in Unix-based operating systems. One of the fundamental constructs in Bash programming is the if statement. The if statement allows you to control the flow of your script based on specific conditions. In this article,...
= STRIN2 # Trueifstrings arenotequal#算术测试操作var1 -eq var2 # Trueifvar1 is equal to var2var1 -ne var2 # Trueifvar1notequal to var2var1 -lt var2 # Trueifvar1 is less than var2var1 -le var2 # Trueifvar1 is less thanorequal ...
Bash string comparison It is advisable always to check and compare if two strings are equal in a Bash script; this is quite important for different reasons. If two strings are equal in a Bash script, it implies that both strings have the same length and character sequence. The “if” stat...
In this example, we have two variables, ‘a’ and ‘b’. The script checks if ‘a’ is equal to ‘b’. If it’s not, it moves on to the ‘elif’ statement to check if ‘a’ is greater than ‘b’. If neither condition is met, it executes the ‘else’ statement, which in ...
[ STRING1 > STRING2 ] 如果 “STRING1” sorts after “STRING2” lexicographically in the current locale则为真。 [ ARG1 OP ARG2 ] “OP” is one of -eq, -ne, -lt, -le, -gt or -ge. These arithmetic binary operators return true if “ARG1” is equal to, not equal to, less than...
String Not Equal To [[ $fruit != "banana" ]] ! Not [[ ! "apple" =~ ^b ]] If和Else 条件表达式的功能非常强大,因为我们可以使用它们来控制正在编写的Bash程序的执行方式。Bash编程中的基本构造之一是IF语句。在IF语句中编写的代码只在某个条件为真时执行,否则代码将被跳过。让我们写一个带有IF语句...
An expression can be: String comparison, Numeric comparison, File operators and Logical operators and it is represented by [expression]: Number Comparisons: -eq - is equal to - if [ "$a" -eq "$b" ] -ne - is not equal to - if [ "$a" -ne "$b" ] -gt - is greater than - ...
/bin/BashS1="Hello World"S2="Hello World"if["$S1"="$S2"]thenecho"Equal"elseecho"Not Equal"fi The following script contains two strings, S1 and S2, that have the same value. The if condition uses the = operator to compare the strings; however, we can also useif [ "$S1" == "...