Question

我在元组中有一个表格列表，格式如下，当前页面为 CurrPageName = "ihtx_f_10_00_00_00_00_h210401".

FormList = {form_list, [{"IHTX_F_10_00_00_00_00_H210401",true},
                        {"IHTX_F_09_00_00_00_00_H210401",true},
                        {"IHTX_F_11_11_02_02_01_H220401",true},
                        {"IHTX_F_03_00_00_00_00_H210401",false},
                        {"IHTX_F_12_00_00_00_00_H211215",true},
                        {"IHTX_F_07_00_00_00_00_H210401",true},
                        {"IHTX_F_15_00_00_00_00_H210401",false},
                        {"IHTX_F_11_00_00_00_00_H210401",false},
                        {"IHTX_F_02_00_00_00_00_H210401",true},
                        {"IHTX_F_01_00_00_00_00_H240401",true}]}.

如何从FormList中找到CurrPageName？我尝试了list：keyfind，keysearch到内部列表，但总是返回false或者一些错误。如果CurrPageName存在且其值为true，则只应返回true else else。

我是二郎的新手。感谢

Answer 1

该列表将页面名称存储为大写字符串，因此首先要确保您的CurrPageName变量也包含大写字符串

CurrPageName = string:to_upper("ihtx_f_10_00_00_00_00_h210401").

然后提取元组列表并搜索页面

{form_list, L} = FormList, % Extract tuple list to L
KeyPosition=1,             % The name we look for is at position 1 in the tuple
T=lists:keyfind(CurrPageName, KeyPosition, L),
case T of
 {_Key, true} ->
    true ;
 false ->
    false
end.

Answer 2

您可以使用proplists。

CurrPageName = string:to_upper("ihtx_f_10_00_00_00_00_h210401").
{form_list, L} = FormList, 
Res = proplists:is_defined(CurrPageName, L)

搜索关键的erlang

2 个答案: