Time,Date

time api
<br />change #可以直接改時間ㄟ<br />last_month<br />next_week<br />seconds_since_midnight #從凌晨到現在的秒數<br />advance #等同since<br />days_in_month #秀哪個月幾天<br />#String 有<br />to_time, to_date <br />

sql,DATE,group by

想要計算某些column 每天的總數時, 可以用sql 的DATE<br />#select 出這個月份每天的render 數<br />>> Render.count(:all, :conditions => {:created_at => Time.now.beginning_of_month..Time.now}, :group => 'DATE(created_at)')<br /><br />SELECT count(*) AS count_all, DATE(created_at) AS date_created_at FROM `renders` WHERE (`renders`.`created_at` BETWEEN '2008-12-01 00:00:00' AND '2008-12-17 16:09:20') GROUP BY DATE(created_at)<br /><br />=> [["2008-12-16", 1], ["2008-12-17", 24]]<br />
結果出來是 OrderedHash 所以要用
hash["2008-12-16"] 去取值, 當然hash 的相關method 也可以用

sql,DATE,group by

想要計算某些column 每天的總數時, 可以用sql 的DATE<br />#select 出這個月份每天的render 數<br />>> Render.count(:all, :conditions => {:created_at => Time.now.beginning_of_month..Time.now}, :group => 'DATE(created_at)')<br /><br />SELECT count(*) AS count_all, DATE(created_at) AS date_created_at FROM `renders` WHERE (`renders`.`created_at` BETWEEN '2008-12-01 00:00:00' AND '2008-12-17 16:09:20') GROUP BY DATE(created_at)<br /><br />=> [["2008-12-16", 1], ["2008-12-17", 24]]<br />
結果出來是 OrderedHash 所以要用
hash["2008-12-16"] 去取值, 當然hash 的相關method 也可以用

js, getMonth, getDate, getDay, date

JavaScript Date Object Reference
<br /> getMonth() //get 出來的是0~11 0是1月 11是12月<br /> getDate() //get 出來的是日期<br /> getDay() //get 出來的是星期 0~6 Sunday is 0, Monday is 1<br />

string, to_time, parse

想把字串變成time object

>> ('2004/01/2').to_time
=> Fri Jan 02 00:00:00 UTC 2004 <<= 有UTC

>> Time.parse('2004/01/2')
=> Fri Jan 02 00:00:00 +0800 2004

取得 select_date 所設定的值, 範圍 prefix

View
<% form_for :task ,:url => {:action => 'query_date_tasks' } do |form|%>
　Query Date between
　<%= select_date Date.today, :prefix => "stay_from", :include_blank => true %>

and
<%= select_date Date.today, :prefix => "stay_to", :include_blank => true %>
<%= submit_tag "submit" %>
<% end %>

:prefix 用來設定參數的名稱
:params => { :stay_from => { :year => 2007, :month => 12, :day => 5}}


Controller

def query_date_tasks
　date_stay_from = Date.new(params[:stay_from][:year].to_i,
　　　　　　　　　　　　　　　params[:stay_from][:month].to_i,
　　　　　　　　　　　　　　　params[:stay_from][:day].to_i)

　date_stay_to = Date.new(params[:stay_to][:year].to_i,
　　　　　　　　　　　　　params[:stay_to][:month].to_i,
　　　　　　　　　　　　　params[:stay_to][:day].to_i)

　@tasks = Task.find(:all, :conditions => ["finish_time BETWEEN ? AND ?", date_stay_from, date_stay_to])

　render :action => 'list_all_tasks'
end