Shell script selection structure (1)

Bash selection Structure
Select the program structure to determine the given conditions, determine certain conditions based on the judgment results, and control the program process based on the judgment results. (For details about how to use the structure selected in shell scripts, refer to the help Documentation)

If statement Structure
(1) If judgment condition; then
Command
Fi

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(2) If judgment condition; then
Command
Else
Command

Fi

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(3) If judgment conditions; then
Command
Elif judgment condition; then
Command
...
Else
Command
Fi

Use and nesting of multiple branches of IF Statements

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Case statement
Case variable in
Pattern1) command ;;
...
*) Command ;;
ESCA

Simple use of case and nested with IF Statements

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This article from the "rookie road forward" blog, please be sure to keep this source http://8381039.blog.51cto.com/8371039/1534250