Question

假设我在视图中有以下rails代码：

    <%= form.select(:language_id,
        options_from_collection_for_select(Language.all, :id, :name),
        {},
        { :onchange => "setThemeAndMode('theme', 'mode')", class: "form-control" })
    %>

是否可以在onchange事件中向language.theme调用发送language.mode和setThemeAndMode？或者甚至将特定的language模型元素作为一些扁平的json？

Answer 1

我很难按照你的意愿行事，但这里有一个我认为你在问的东西。

如果您知道渲染时的值，则可以插入onchange字符串。

   char* widen_stars(char * str1, char *str2)
{       
    int ls1 = strlen(str1);
    int ls2 = strlen(str2);

    char *str4 = (char *) malloc(strlen(str1) + strlen(str2)+ 29);
    char *p1 = str1;
    char *p2 = str2;
    char *p3 = str4;
    char *asterix;
    *asterix = '*'; //Pointer pointing to *, won't let me though//
        while(*p1 != '\0'){
        *p3 = *p1;
        p1++;
        p3++;
        *p3 = *asterix; // Needs to add an *, after printing the first element.//
        }
        while(*p2 != '\0'){
        *p3 = *p2;
        p2++;
        p3++;
        *p3 = *asterix;
        }
    return str4;
}

如果您尝试获取select元素新更改的值的值，则需要在javascript中获取select元素的值。

<%= form.select(:language_id,
    options_from_collection_for_select(Language.all, :id, :name),
    {},
    { :onchange => "setThemeAndMode('#{Mything}', '#{other thing}')", class: "form-control" })
%>

Answer 2

正如您在Rails's document中所看到的，您可以将块传递给select，以自定义选项标记的呈现方式。

form.select :language_id do
  Language.all.each do |lang|
    content_tag(:option, c.name, value: c.id,
      onchange: "setThemeAndMode('#{get_theme_logic}', '#{get_mode_logic}')")
  end
end

您还可以定义帮助程序以呈现content_tag以使代码更清晰

将Rails模型参数传递给javascript onchange调用？

2 个答案: