Shell有判断变量是否为整型,字符,字符串等的函数吗?

xwmhmily

Shell有判断变量是否为整型,字符,字符串等的函数吗?

寂寞烈火

shell不提供此项功能,不过bash有个declare可以强制一个变量为整数

walkerxk

含有非数字就是字符或者字符串，长度大于一就是字符串：
echo $a|sed 's/[0-9]//g'|wc -c去掉数字后的长度，如果是0就是整型
echo $a|wc -c变量长度，如果是1就是字符，否则就是字符串
但是科学计数法就没发判断了，不过我想用的不多，如果要包含小数的话可以把[0-9]改成[0-9.]，但是对于1.2.3这类就麻烦了，要用^[0-9]+(.[0-9]+)?$来判断，其实正则的话，够用就好。

springwind426

bash

1. 
   
2. #!/bin/bash
   
3. function check(){
   
4.         local a="$1"
   
5.         printf "%d" "$a" &>/dev/null && echo "integer" && return
   
6.         printf "%f" "$a" &>/dev/null && echo "number" && return
   
7.         [ ${#a} -eq 1 ] && echo "char" && return
   
8.         echo "string"
   
9. }
   
10. 
    
11. echo ". is" $(check ".")
    
12. echo "1 is" $(check "1")
    
13. echo ".1 is" $(check ".1")
    
14. echo "1. is" $(check "1.")
    
15. echo "1234 is" $(check "1234")
    
16. echo "1.234 is" $(check "1.234")
    
17. echo "1.2.3.4 is" $(check "1.2.3.4")
    
18. echo "a1234 is" $(check "a1234")
    
19. echo "abc is" $(check "abc")
    
20. echo "a is" $(check "a")
    
21. echo "1e+2" $(check "1e+2")
    
22. echo "1.e+2" $(check "1e+2")
    
23. echo ".1e+2" $(check "1e+2")
    
24. echo "-1" $(check "-1")
    
25. echo "-1.2" $(check "-1.2")
    
26. echo "-a" $(check "-a")
    

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[ 本帖最后由 springwind426 于 2008-7-8 11:42 编辑 ]

edei2004

学习了

springwind426

修改一下，增加一些异样数据的检测

1. 
   
2. #!/bin/bash
   
3. function check(){
   
4.         local a="$1"
   
5.         printf "%d" "$a" &>/dev/null && echo "integer" && return
   
6.         printf "%d" "$(echo $a|sed 's/^[+-]\?0\+//')" &>/dev/null && echo "integer" && return
   
7.         printf "%f" "$a" &>/dev/null && echo "number" && return
   
8.         [ ${#a} -eq 1 ] && echo "char" && return
   
9.         echo "string"
   
10. }
    
11. 
    
12. echo ". is" $(check ".")
    
13. echo "1 is" $(check "1")
    
14. echo ".1 is" $(check ".1")
    
15. echo "1. is" $(check "1.")
    
16. echo "1234 is" $(check "1234")
    
17. echo "1.234 is" $(check "1.234")
    
18. echo "1.2.3.4 is" $(check "1.2.3.4")
    
19. echo "a1234 is" $(check "a1234")
    
20. echo "abc is" $(check "abc")
    
21. echo "a is" $(check "a")
    
22. echo "1e+2" $(check "1e+2")
    
23. echo "1.e+2" $(check "1e+2")
    
24. echo ".1e+2" $(check "1e+2")
    
25. echo "-1" $(check "-1")
    
26. echo "-1.2" $(check "-1.2")
    
27. echo "-a" $(check "-a")
    
28. echo "0x1f" $(check "0x1f")
    
29. echo "0x1H" $(check "0x1H")
    
30. echo "0333" $(check "0333")
    
31. echo "0999" $(check "0999")
    
32. echo "+003" $(check "+003")
    
33. echo "+003.3" $(check "+003.3")
    

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[ 本帖最后由 springwind426 于 2008-7-8 11:55 编辑 ]