在单选按钮上捕获名称？

Question

作为编码的大新手，我如何使以下部分正常工作？ 我想捕获RadioButton 的Text。

例如

radio1.Text = weekly

radio2.Text = monthly

// Doesn't compile; to show the requirement only
if (radio1.checked) then 3
  write weekly
else if (radio2.checked) then 
  write monthly

// write to txt file 
var line = string.Join(Environment.NewLine,
  $"First Name:               {tfirstn.Text}",
  $"Last Name:                {tlastn.Text}",
  $"Address:                  {taddr.Text}",
  $"Mobile Number:            {tmobi.Text}",
  $"Recurring Payment Amount: {rpabox.Text}",
  $"Account Number:           {taccnbr.Text}",
   // this should display "weekly" or "monthly" depending on radio button checked
  $"Frequency:                {}", 
  $"",
  $"",
   ""
);

Answer 1

假设 所有 感兴趣的单选按钮在 same 容器中，例如myPanel，你可以试试Linq：在容器中的所有RadioButtons中（Daily，Weekly，Monthly，Yearly等），让我们找到取出First 一个Checked，取其Text（如果所有RadioButtons 都未选中，则返回"???"）

using System.Linq;

...

radio1.Text = "Weekly";
radio2.Text = "Monthly";

...

string frequency = myPanel // put "this" if radiobuttons are on the form
  .Controls
  .OfType<RadioButton>()
  .FirstOrDefault(rb => rb.Checked)
 ?.Text ?? "???"; // "???" - if none radiobutton is checked

...

var line = string.Join(Environment.NewLine,
  ...
  $"Frequency:                {frequency}", // this should display Weekly or Monthly  
  ...
);

Answer 2

试试这个：

radio1.Checked ? "weekly" : "monthly"

upd：让答案更清楚

var line = string.Join(Environment.NewLine,
              $"First Name:               {tfirstn.Text}",
              $"Last Name:                {tlastn.Text}",
              $"Address:                  {taddr.Text}",
              $"Mobile Number:            {tmobi.Text}",
              $"Recurring Payment Amount: {rpabox.Text}",
              $"Account Number:           {taccnbr.Text}",
              "Frequency:"              + radio1.Checked ? "weekly" : "monthly",
              $"",
              $"",
               ""
            );

如果选择了 radio1，则打印“weekly”，如果选择了 radio2，则打印“monthly”或未选择任何电台