echo "-n $a : The string length is not 0" else echo "-n $a : The string length is 0" fi if [ $a ] then echo "$a : The string is not empty" else echo "$a : The string is empty" fi 结果 abc = efg: a != b -n abc : The string length is not 0 abc : The strin...
str="" if [ "$str" == "" ]; then echo "String is empty" else echo "String is not empty" fi 字符串长度比较:可以使用大于号(>)、小于号(<)来比较两个字符串的长度。例如: 代码语言:txt 复制 str1="Hello" str2="World" if [ ${#str1} -gt ${#str2} ]; then echo "str1 is lo...
echo "The string is not empty." fi 这是我们执行脚本时的结果: 代码语言:txt AI代码解释 $ ./test.sh Strings are different. 例4 -n运算符还可用于测试字符串长度是否不为零。 代码语言:txt AI代码解释 #!/bin/bash string="hello" if [[ -n $string ]]; then echo "The string is not empty...
bash command if a string is not empty examples of the check when DiskInternals can help you Are you ready? Let's read! Variables that are set and not empty A variable is either defined or not defined. However, when a variable is defined but has no value, then the variable is “Not ...
if [[ -n $String ]]; then echo "The variable String is not an empty string." fi 输出: The variable String is not an empty string. 在这个程序中,String 是一个非空变量。由于 -n 运算符返回 true,如果 string 的长度不是 0,因此我们得到 The variable String is not an empty string. 作为...
STRING True if string is not empty. 即,test命令使用-z STRING操作符来判断STRING字符串的长度是否为 0。 如果为 0,就是空字符串,会返回 true。 具体写法是test -z STRING,使用[命令则写为[ -z STRING ]。 -n STRING操作符判断STRING字符串的长度是否为 0。
if[$a]thenecho"$a: The string is not empty"elseecho"$a: The string is empty"fi 文件测试运算符 浮点运算 expr 只能用于整数计算,可以使用 bc 或者 awk 进行浮点数运算。 #!/bin/bashradius=2.4 pi=3.14159 girth=$(echo"scale=4; 3.14 * 2 *$radius"| bc) ...
echo "-n $a : The string length is not 0" else echo "-n $a : The string length is 0" fi if [ $a ] then echo "$a : The string is not empty" else echo "$a : The string is empty" fi 1. 2. 3. 4. 5. 6.
MY_STRING="" if [ -z $MYSTRING ] then echo "String is empty" else echo "String is not empty" fi For more Shell scripting tips,check out or Bash/Shell scripting articles!
if [[ -z "$string" ]]; then echo "String is empty" elif [[ -n "$string" ]]; then echo "String is not empty" fi 字符串引号 str="czx" echo "Hello ${str}" # 显示 Hello czx echo 'Hello ${str}' # 显示 Hello ${str} 函数 get_name() { echo "czx" } echo "My nam...