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,...
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including if, else, and elif. Then we'll look at a few of the "primary" operators you can leverage in a conditional statement such as = for string equality, -eq for numeric equality, and -e to check if a file exists. After that, we'll use conditional statements...
比较bash中的两个字符串变量 bash if-statement 这段代码不断重复“他们是平等的”为什么? #!/bin/bash foo="hello" bar="h" if [[ "$foo"=="$bar" ]]; then echo "they are equal" else echo "they are not equal" fi 发布于 1 年前 ✅ 最佳回答: 条件的工作基于其中的元素数量,这个特定...
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 ...
-eq 等于,如:if [ "a"−eq"b" ] -ne 不等于,如:if [ "a"−ne"b" ] -gt 大于,如:if [ "a"−gt"b" ] -ge 大于等于,如:if [ "a"−ge"b" ] -lt 小于,如:if [ "a"−lt"b" ] -le 小于等于,如:if [ "a"−le"b" ] ...
if [[ $USER = 'username' ]]; then echo "true" else echo "false" fi 1. 2. 3. 4. 5. not equal:!= numeric equality:-eq not equals:-ne is empty:-z if [[ 1 -eq 1 ]]; if [[ -z $USER ]]; 1. 2. 3. Elif if [[ -z $USER ]]; then ...
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。当你使用if或if/elif语句时,它是自上而下工作的。当第一条语句是匹配的时候,它会停...
if [ $NUM1 -eq $NUM2 ]; then echo "Both Values are equal" else echo "Values are NOT equal" fi 1. 2. 3. 4. 5. 6. 7. 8. 9. #!/bin/bash # declare integers NUM1=2 NUM2=1 if [ $NUM1 -eq $NUM2 ]; then echo "Both Values are equal" ...
The condition in the IF statement was true, so only the firstechocommand was executed. Now let’s run the program with5as the first argument: bashsimpleelif.sh 5 ## 5 is a great number The first condition is false since 5 is not equal to 4, but then the next condition in the ELIF...