In Bash scripting, it's often necessary to check if a string contains a specific substring. This can be useful for validating user input, processing text data, or executing certain actions based on the presence or absence of a certain pattern. The process of checking if a string contains a ...
So, you have a long string and you want to check of this string contains a substring in your bash script. There are more than one way to check for substrings in bash shell. I'll show some simple examples first, followed by a cool bash script that uses this concept in a real-world ...
if [[ $string == *Hello* ]]; then echo "The string contains 'Hello'" fi ``` 在上面的示例中,首先定义了一个字符串变量string,然后使用if语句判断该字符串是否包含“Hello”这个子字符串。如果包含,则输出提示信息。需要注意的是,在if语句中双括号“[[”和“]]”用来扩起条件判断表达式,这是Bash sh...
4.2 Searching with case-insensitive string 5. Using awk 6. Using sed with grep Command 7. Conclusion 1. Overview In this article, we will see how to check if output contains String in Bash using grep, Conditional Expressions, awk, sed commands with various options. 2. Introduction to Proble...
#!/bin/bash string="hello world" if [[ $string == *world* ]]; then echo "The string contains the substring 'world'." else echo "The string does not contain the substring 'world'." fi 在这个示例中,if语句检查变量string是否包含子字符串"world"。如果包含,则输出相应的提示信息。 5. 解...
bash shell ——if 条件判断 if 语句格式: 1 2 3 4 5 6 7 8 ifcondition then statements [elifcondition thenstatements. ..] [else statements ] fi 最精简的if命令的语法是:if TEST-COMMANDS; then CONSEQUENT-COMMANDS; fi if条件判断语句可以嵌套,以实现多重条件的检测。关键词 “fi” 表示里层 if...
The following output appears if the script is executed with the string input value: Using the “If -N” Statement Sometimes, it is required to check if a string variable is non-empty or if it contains a string value more than zero length. There are many options in Bash to do this task...
template = Template("{{ name }} {% if 'hello' in name %}contains 'hello'{% endif %}") result = template.render(name="hello world") print(result) 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 4. **判断字符串包含** 运行上面的代码,你将看到输出结果为: ...
I pretty much automated every possible task using Bash shell scripting. Based on my Bash experience, I’ve written Bash 101 Hacks eBook that contains 101 practical examples on both Bash command line and shell scripting. If you’ve been thinking about mastering Bash, do yourself a favor and re...
echo "String does not contain lowercase letters" fi ``` 这段代码将输出 "String contains lowercase letters",因为变量 str 中的字符串包含小写字母。 总的来说,Linux 中的 if 语句和字符串匹配是编写 Bash 脚本时基本的工具之一。通过合理的使用条件判断和字符串匹配,我们可以根据不同的情况来决定程序的执行...