问题描述
集合已被修改；枚举操作可能无法执行"为什么在执行我的以下代码时会出现此错误:
这是我在.Net中的窗口表单应用程序
1.我正在使用Global类读取实例消息并将其显示给Textbox
2.它执行得很好，但有时会在第二个foreach循环中显示类似集合已被修改；枚举操作可能无法执行"之类的错误，例如
"Collection was modified; enumeration operation may not execute " Why this error is coming when execute my below code:
This is my Window Form Application in .Net
1.I am using a Global class for reading instance message and shown it to a Textbox
2.It is executing fine but some time showing error like "Collection was modified; enumeration operation may not execute " in second foreach looping like
foreach (var values in dict[item])
{
3.我的全局类是在其中将值存储在Dictionary对象中并从中检索的.
3. My global Class is in which i am storing value in Dictionary object and retrived from that .
public static class GlobalVariables
{
public static Dictionary<string,>> dictionary = new Dictionary<string,>>();
public static void SetMessage(String DBName, String Message)
{
if (dictionary.ContainsKey(DBName))
{
//dictionary.Remove(DBName);
List<string> list = new List<string>();
list.Clear();
list.Add(Message);
dictionary[DBName]=list;
}
else
{
List<string> list = new List<string>();
list.Add(DateTime.Now.ToString());
dictionary.Add("Process Started",list);
}
}
}
4.在这里，我们可以在字典对象的文本框中显示消息，并在第二个foreach行中显示错误，例如
4.Here we can show the message in textbox from Dictionary object and error shown in the second foreach line like
foreach (var values in dict[item])
{
public void setTextBoxValue()
{
//Thread.Sleep(1000);
Dictionary<string, List<string>> dict = GlobalVariables.dictionary;
//string strMessage = Convert.ToString(GlobalVariables.message);
if (dict.Keys.Count > 0)
{
builder.Remove(0, builder.Length);
foreach (var item in dict.Keys)
{
foreach (var values in dict[item])
{
string message = item + ":" + values.ToString();
builder.AppendLine(message);
builder.Append("\n\n");
textBox1.Text = builder.ToString();
}
}
Application.DoEvents();
}
}推荐答案
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