C# 在 if 语句中使用下拉列表的选定值
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Using the selected value of a dropdown list in an if statement
提问by John
I'm trying to select the value from this drop down list to use in an if statement so that I can then do calculations based on which choice is chosen. I'm not sure if this is the right way to do it, any help would be much appreciated!
我正在尝试从此下拉列表中选择要在 if 语句中使用的值，以便我可以根据选择的选项进行计算。我不确定这是否是正确的方法，任何帮助将不胜感激！
<asp:DropDownList ID="ddlHours" runat="server">
<asp:ListItem >Select</asp:ListItem>
<asp:ListItem >Part-Time</asp:ListItem>
<asp:ListItem >Full-Time</asp:ListItem>
</asp:DropDownList>
const int PART_TIME = 15;
const int FULL_TIME = 25;
double fee = 0;
if (ddlHours.SelectedItem.Value == "Part-Time")
{
CalculatePartTime(PART_TIME, fee);
}
else if (ddlHours.SelectedItem.Value == "Full-Time")
{
CalculateFullTime(FULL_TIME, fee);
}
lblAnswer.Text = String.Format("{0}",fee);
采纳答案by Jonysuise
I would use :
我会用：
if (ddlHours.SelectedItem.Text == "Part-Time")
回答by COLD TOLD
it looks like you are not looking for value you are looking for text
看起来您不是在寻找价值，而是在寻找文本
if(ddlHours.SelectedItem.Text == "Part-Time")
回答by Chris Brickhouse
if you open to javascript/jquery, you could do this:
如果你打开 javascript/jquery，你可以这样做：
var PART_Time = 15;
var FULL_TIME = 25;
var fee = 0;
$('#ddlHours').change(function() {
var $this = $(this);
if ($this.val() == 'Part-Time') {
$('#labelAnswer').val(CalculatePartTime(PART_TIME, fee);
}
else {
$('#labelAnswer').val(CalculateFullTime(FULL_TIME, fee);
}
});
i know this doesn't answer your specific question but this would reduce postbacks.
我知道这不能回答您的具体问题，但这会减少回发。
