[ `expr match $line $UBOOT_FOLDER` == "$UBOOT_FOLDER_LEN" ];then echo "$count : right push path" src_path=${T_FOLDER}${line} dst_path=${COMMON_PATH}${line} func_update_file_by_path $src_path $dst_path else echo "$count : push file $line is invalidate!" fi done < $in...
在if语句中,我们喜欢用if [ expression ]; then ... fi的单括号的形式,但看大神们的脚本,他们更常用if [[ expression ]]; then ... fi的双括号形式。 [ ... ]等效于test命令,而[[ ... ]]是另一种命令语法,相似功能却更高级,它除了传统的条件表达式(Eg. [ ${val} -eq 0 ])外,还支持表达式...
在if语句中,我们喜欢用if [ expression ]; then ... fi的单括号的形式,但看大神们的脚本,他们更常用if [[ expression ]]; then ... fi的双括号形式。 [ ... ]等效于test命令,而[[ ... ]]是另一种命令语法,相似功能却更高级,它除了传统的条件表达式(Eg. [ ${val} -eq 0 ])外,还支持表达式...
# Single-line if [[ 2 -ne 1 ]]; then echo "true"; else echo "false"; fi # Multi-line if [[ 2 -ne 1 ]]; then echo "true" else echo "false" fiSometimes if..else statements are not enough to do what we want to do. In this case we shouldn't forget about the existence ...
'Else if'in bash scripting, often written as'elif', is used to check multiple conditions in your code. It is used with the syntax,if [firstStatement]; then... elif [secondCondition]; then... else. It’s a powerful tool that allows your scripts to make decisions based on various scen...
使用If Then Else 确定变量是否为 NULL 若要评估字符串,请使用!=;若要评估数字,请使用-ne。 以下 If Then Else 语句评估是否已设置 $resourceGroup 变量。 如果是,则返回变量的值。 如果否,则设置变量。 Azure CLI if [$resourceGroup!='']; then echo$resourceGroupelseresourceGroup="msdocs-learn-bash-...
有人喜欢用这种格式来代替 if...then...else 结构,但其实并不完全一样。如果cmd2返回一个非真值,那么cmd3则会被执行。所以还是老老实实地用 if cmd1; then cmd2; else cmd3 为好。 21. UTF-8的BOM(Byte-Order Marks)问题 UTF- 8编码可以在文件开头用几个字节来表示编码的字节顺序,这几个字节称为BO...
if then else fi Used to test a condition and use a fallback if the test fails. if then elif else fi Used to test a condition and use a fallback if all tests fail. for do done Iterate over a list of values. while do done Used to performs a given set of commands an unknown numb...
if语法更短 # One line # Note: The 3rd statement may run when the 1st is true [[ $var == hello ]] && echo hi || echo bye [[ $var == hello ]] && { echo hi; echo there; } || echo bye # Multi line (no else, single statement) ...
# Single-line if [[ 2 -ne 1 ]]; then echo "true"; else echo "false"; fi # Multi-line if [[ 2 -ne 1 ]]; then echo "true" else echo "false" fiSometimes if..else statements are not enough to do what we want to do. In this case we shouldn't forget about the existence ...