freemarker中的left_pad和right_pad

freemarker中的left_pad和right_pad

1、简易说明

（1）left_pad 距左边

（2）right_pad 距右边

（3）当仅仅只有一个参数时，插入的是空白；当有两个参数时，插入的是第二个参数符号；如果第二个参数的长度大于1的话，会周期性地插入该符号

2、举例说明

<#--freemarker中的left_pad 距左边-->
     [${""?left_pad(8)}]
     [${"E"?left_pad(8)}]
     [${"EF"?left_pad(8)}]
     [${"EFG"?left_pad(8)}]
     [${"EFGH"?left_pad(8)}]
     [${"EFGHI"?left_pad(8)}]
     [${"EFGHIJ"?left_pad(8)}]
     [${"EFGHIJK"?left_pad(8)}]
     [${"EFGHIJKL"?left_pad(8)}]

     [${""?left_pad(8,"*")}]
     [${"E"?left_pad(8,"*")}]
     [${"EF"?left_pad(8,"*")}]
     [${"EFG"?left_pad(8,"*")}]
     [${"EFGH"?left_pad(8,"*")}]
     [${"EFGHI"?left_pad(8,"*")}]
     [${"EFGHIJ"?left_pad(8,"*")}]
     [${"EFGHIJK"?left_pad(8,"*")}]
     [${"EFGHIJKL"?left_pad(8,"*")}]

     [${""?left_pad(8,"?*?")}]
     [${"E"?left_pad(8,"?*?")}]
     [${"EF"?left_pad(8,"?*?")}]
     [${"EFG"?left_pad(8,"?*?")}]
     [${"EFGH"?left_pad(8,"?*?")}]
     [${"EFGHI"?left_pad(8,"?*?")}]
     [${"EFGHIJ"?left_pad(8,"?*?")}]
     [${"EFGHIJK"?left_pad(8,"?*?")}]
     [${"EFGHIJKL"?left_pad(8,"?*?")}]

     <#--freemarker中的right_pad 距右边-->
     [${""?right_pad(8)}]
     [${"E"?right_pad(8)}]
     [${"EF"?right_pad(8)}]
     [${"EFG"?right_pad(8)}]
     [${"EFGH"?right_pad(8)}]
     [${"EFGHI"?right_pad(8)}]
     [${"EFGHIJ"?right_pad(8)}]
     [${"EFGHIJK"?right_pad(8)}]
     [${"EFGHIJKL"?right_pad(8)}]

     [${""?right_pad(8,"*")}]
     [${"E"?right_pad(8,"*")}]
     [${"EF"?right_pad(8,"*")}]
     [${"EFG"?right_pad(8,"*")}]
     [${"EFGH"?right_pad(8,"*")}]
     [${"EFGHI"?right_pad(8,"*")}]
     [${"EFGHIJ"?right_pad(8,"*")}]
     [${"EFGHIJK"?right_pad(8,"*")}]
     [${"EFGHIJKL"?right_pad(8,"*")}]

     [${""?right_pad(8,"?*?")}]
     [${"E"?right_pad(8,"?*?")}]
     [${"EF"?right_pad(8,"?*?")}]
     [${"EFG"?right_pad(8,"?*?")}]
     [${"EFGH"?right_pad(8,"?*?")}]
     [${"EFGHI"?right_pad(8,"?*?")}]
     [${"EFGHIJ"?right_pad(8,"?*?")}]
     [${"EFGHIJK"?right_pad(8,"?*?")}]
     [${"EFGHIJKL"?right_pad(8,"?*?")}]

3、示例结果

     [        ]
     [       E]
     [      EF]
     [     EFG]
     [    EFGH]
     [   EFGHI]
     [  EFGHIJ]
     [ EFGHIJK]
     [EFGHIJKL]

     [********]
     [*******E]
     [******EF]
     [*****EFG]
     [****EFGH]
     [***EFGHI]
     [**EFGHIJ]
     [*EFGHIJK]
     [EFGHIJKL]

     [?*??*??*]
     [?*??*??E]
     [?*??*?EF]
     [?*??*EFG]
     [?*??EFGH]
     [?*?EFGHI]
     [?*EFGHIJ]
     [?EFGHIJK]
     [EFGHIJKL]

     [        ]
     [E       ]
     [EF      ]
     [EFG     ]
     [EFGH    ]
     [EFGHI   ]
     [EFGHIJ  ]
     [EFGHIJK ]
     [EFGHIJKL]

     [********]
     [E*******]
     [EF******]
     [EFG*****]
     [EFGH****]
     [EFGHI***]
     [EFGHIJ**]
     [EFGHIJK*]
     [EFGHIJKL]

     [?*??*??*]
     [E*??*??*]
     [EF??*??*]
     [EFG?*??*]
     [EFGH*??*]
     [EFGHI??*]
     [EFGHIJ?*]
     [EFGHIJK*]
     [EFGHIJKL]