检查DatePicker值是否为null

时间:2016-03-12 12:48:46

标签: c# wpf datepicker wpf-controls

我想检查DatePicker的值是否为空(==框中没有日期)。

默认情况下,Text的{​​{1}}设置为DatePicker,因此我无法使用Select a date属性进行检查。

3 个答案:

答案 0 :(得分:9)

DatePicker类有一个属性SelectedDate,可用于获取或设置所选日期。如果没有选中,则表示其值为null。

>>> py_compile.compile('test.py')
  File "hello_world.py", line 1
    print "Hello World")
                   ^
SyntaxError: invalid syntax

答案 1 :(得分:2)

虽然DatePicker的默认文本为Select a date,但您可以使用Text属性来Text.Length进行检查。或者像这样检查SelectedDate属性:

if (datePicker.Text.Length == 0)
{
    //Do your stuff        
}

或者:

if (datePicker.SelectedDate == null)
{
    //Do your stuff
}

答案 2 :(得分:0)

to = $('#to');// hopefully you defined this yourself and the options
//I am writing coffeeScript here, below I will add pure JS

if to.datepicker('getDate') == null
  //basically do your stuff here - 
  //using month_day_year_string (m_d_y_s) func to format a date object here and add 6 to the date's year so passed e.g. 2014 gives 2020.
  return to.datepicker('option', 'minDate', getDate(this), to.datepicker('option', 'maxDate', m_d_y_s(getDate(this), 6)))
return// I have this on a call back so I am returning from the call back

在纯JS中,它简直就是

var to = $('#to');// hope you defined the options and datepicker
if (to.datepicker('getDate') === null) {
  #do your stuff - I have an example code below as I needed this check in a callback
  return to.datepicker('option', 'minDate', getDate(this), to.datepicker('option', 'maxDate', m_d_y_s(getDate(this), 6)));
 }

return;// if on a call back e.g. onChange or onRender.