解决方法:使用 = 进行严格相等性比较,或者对字符串进行引用,例如 "${string1}" == "${string2}"。 示例代码 代码语言:txt 复制 #!/bin/bash string1="hello" string2="world" if [ "${string1}" = "${string2}" ]; then echo "Strings are equal." else echo "Strings are not equal." ...
boolean equalsIgnoreCase(String anotherString) 将此String 与另一个 String 进行比较,不考虑大小写。 if (s1.equals(s2)) { } 注意:一定要保证s1 != null,否则会抛出异常。 StringUtils.equals & StringUtils.equalsIgnoreCase 在Apache Commons Lang中的StringUtils类提供了equals和equalsIgnoreCase静态方法,它的好处是...
为什么80%的码农都做不了架构师?>>> 1、字符串不变性 下面这张图展示了这段代码做了什么 1 2 String s ="abcd"; s = s.concat("ef"); 2、equals()方法、hashCode()方法的区别 HashCode被设计用来提高性能。equals()方法与hashC... 概念介绍:POE供电交换机、tcpip模型、OSI七层模型、路由协议、网关...
-n string: True if the length of the string is greater than zero. -z string: True if the length of the string is zero. That is, it's an empty string. string1 = string2: True if string1 is the same as string2. string1 != string2: True if string1 is not the same as string...
How to do string comparison and check if a string equals to a value? 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...
TestFile1 does not exist or is empty. 向文件添加一些内容,然后再测试一次: [student@studentvm1 testdir]$ File="TestFile1" ; echo "This is file $File" > $File ; if [ -s $File ] ; then echo "$File exists and contains data." ; else echo "$File does not exist or is empty." ...
In this case, the expression is slightly different, instead of typing true or false, thestdoutvariable is printed using$?. Check if strings are not equals The!=operator checks if String1 is not equal to String2. If the two strings are not equal, then it returns 0. If two strings are...
如果if结构使用的不是test命令,而是普通命令,比如上一节的((...))算术运算,或者test命令与普通命令混用,那么可以使用 Bash 的命令控制操作符&&(AND)和||(OR),进行多个命令的逻辑运算。$ command1 && command2 $ command1 || command2对于&&操作符,先执行command1,只有command1执行成功后, 才会执行command2。
\2. 在if分支中作为占位符(即某一分支什么都不做的时候); \3. 放在必须要有两元操作的地方作为分隔符,如:: ${username=whoami} \4. 在参数替换中为字符串变量赋值,在重定向操作(>)中,把一个文件长度截断为0(:>>这样用的时候,目标存在则什么都不做),这个只能在普通文件中使用,不能在管道,符号链接和其...
/bin/BashS1="Hello World"S2="Hello World"if["$S1"="$S2"]thenecho"Equal"elseecho"Not Equal"fi The following script contains two strings,S1andS2have the same value. Theifcondition compare the string using=operator; however, we can also useif [ "$S1" == "$S2" ]statement to compare...