Shell Script ——— Compare integer size classic case

Method 1: Pass the parameter

#!/bin/bash

##############################################################

# File Name:compare1.sh

# version:v7.4

# Author:feng Yu

# organization:http://blog.51cto.com/13520761

# Created Time:2018-03-26 17:22:20

# Description:

##############################################################

[$#-ne 2] && echo "Please enter 2 parameters" && Exit 2 ---The number of parameters is not equal to 2 o'clock, please enter 2 parameters and exit

Expr + 1 &>/dev/null

[$?-eq 2] && echo "Please enter integer" && exit 2 ---Determine if the first argument is an integer, not an integer, enter an integer, and exit

Expr + 1 &>/dev/null

[$?-eq 2] && echo "Please enter integer" && exit 2 ---Determine if the second argument is an integer, not an integer, enter an integer, and exit

[$1-eq] && echo "$ = $"

[$1-LT] && echo "$ < $"

[$1-GT] && echo "$ > $"

Method 2: Pass the parameter (if expression)

#!/bin/bash

##############################################################

# File Name:compare.sh

# version:v7.4

# Author:feng Yu

# organization:http://blog.51cto.com/13520761

# Created Time:2018-03-26 16:20:43

# Description:

##############################################################

if! [$#-eq 2];then

echo "Please enter 2 parameters"

Exit

Fi

Expr + 1 &>/dev/null

If [$?-eq 2];then

echo "Please enter an integer"

Exit

Fi

Expr + 1 &>/dev/null

If [$?-eq 2];then

echo "Please enter an integer"

Exit

Fi

If [$1-eq $];then

echo "$ = $"

elif [$1-lt $];then

echo "$ < $"

elif [$1-gt $];then

echo "$ > $"

Fi

Method 3:read Read in

#!/bin/bash

##############################################################

# File Name:compare2.sh

# version:v7.4

# Author:feng Yu

# organization:http://blog.51cto.com/13520761

# Created Time:2018-03-26 18:20:14

# Description:

##############################################################

Read-p "Please enter an integer:" Num1

Expr $num 1 + 1 &>/dev/null

[$?-eq 2] && echo "Please enter an integer" && exit 2

[-Z] $num 1 "] && echo" Please enter an integer "&& exit 2

Read-p "Please enter an integer:" num2

Expr $num 2 + 1 &>/dev/null

[$?-eq 2] && echo "Please enter an integer" && exit 2

[-Z] $num 2 "] && echo" Please enter an integer "&& exit 2

[$num 1-eq $num 2] && echo "$num 1 = $num 2"

[$num 1-gt $num 2] && echo "$num 1 > $num 2"

[$num 1-lt $num 2] && echo "$num 1 < $num 2"

Method 4:read Read-in (if expression)

#!/bin/bash

##############################################################

# File Name:compare2.sh

# version:v7.4

# Author:feng Yu

# organization:http://blog.51cto.com/13520761

# Created Time:2018-03-26 18:20:14

# Description:

##############################################################

Read-p "Please enter an integer:" Num1

Expr $num 1 + 1 &>/dev/null

If [$?-eq 2];then

echo "Please enter an integer"

Exit 2

Fi

If [-z] $num 1 "];then

echo "Please enter an integer"

Exit 2

Fi

Read-p "Please enter an integer:" num2

Expr $num 2 + 1 &>/dev/null

If [$?-eq 2];then

echo "Please enter an integer"

Exit 2

Fi

If [-Z] $num 2 "];then

echo "Please enter an integer"

Exit 2

Fi

If [$num 1-eq $num 2];then

echo "$num 1 = $num 2"

elif [$num 1-gt $num 2];then

echo "$num 1 > $num 2"

elif [$num 1-lt $num 2];then

echo "$num 1 < $num 2"

Fi

Shell Script ——— Compare integer size classic case