C# 如何检查表单是否打开，如果打开关闭表单？
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How to check if form is open, if open close form?
提问by Edwin Torres
How do I check if a form is open, and if it is open to close the form?
如何检查表单是否已打开，以及是否已打开以关闭表单？
I tried the following, testing out some code but it keep saying the form is not open even when I know it is:
我尝试了以下操作，测试了一些代码，但它一直说即使我知道表单没有打开：
foreach(Form a in Application.OpenForms)
{
if (a is YouLikeHits_Settings)
{
// About form is open
MessageBox.Show("form open");
break;
}
// About form is not open...
MessageBox.Show("form not open");
break;
}
采纳答案by Sergey Berezovskiy
Application.OpenFormscontains opened forms. If form in this collection, then it is opened. Otherwise it is not opened (possibly closed).
Application.OpenForms包含打开的表单。如果表单在此集合中，则将其打开。否则它不会打开（可能关闭）。
if (Application.OpenForms.OfType<YouLikeHits_Settings>().Any())
MessageBox.Show("Form is opened");
else
MessageBox.Show("Form is not opened");
回答by Nitin...
This will work sure
这肯定会起作用
if (Application.OpenForms.OfType<frm_YouLikeHits_Settings>().Any())
{
Application.OpenForms.OfType<frm_YouLikeHits_Settings>().First().Close();
}
frm_YouLikeHits_Settings f1= new frm_YouLikeHits_Settings();
f1.MdiParent = this;
f1.Show();
回答by John G
try
{
if (Application.OpenForms.OfType<talkForm>().Any())
{
talkForm frm = new talkForm();
frm.Close();
MessageBox.Show("Form is opened");
}
else
{
talkForm frm = new talkForm();
frm.Show();
MessageBox.Show("Form is not opened");
}
}
catch(Exception ex)
{
}
