我有这段代码,我单击 Delete 键,它应该从 listBox 中删除一个项目:
private void listBox1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Delete)
{
if (this.listBox1.SelectedIndex >= 0)
this.listBox1.Items.RemoveAt(this.listBox1.SelectedIndex);
}
}
但是,只要我按下删除键,我就会在 RemoveAt 行出现错误:
设置 DataSource 属性时无法修改项目集合。
现在我在 Form1 的其他两个地方使用了 DataSource: 首先:
private void ListBoxLoadKeys(Dictionary<string, List<string>> dictionary, string FileName)
{
using (StreamReader sr = new StreamReader(FileName))
{
while ((line = sr.ReadLine()) != null)
{
int i = line.Count();
tokens = line.Split(',');
dictionary.Add(tokens[0], tokens.Skip(1).ToList());
data.Add("Url: " + tokens[0] + " --- " + "Localy KeyWord: " + tokens[1]);
}
}
listBox1.DataSource = data;
}
第二个地方:
private void ClearListBox()
{
data.Clear();
listBox1.DataSource = null;
string sb;
foreach (KeyValuePair<string, List<string>> kvp in LocalyKeyWords)
{
for (int i = 0; i < kvp.Value.Count(); i++)
{
sb = "Url: " + kvp.Key + " --- " + "Local KeyWord: " + kvp.Value[i] + Environment.NewLine;
data.Add(sb.ToString());
}
}
listBox1.DataSource = data;
listBox1.Select();
}
那么我可以使用什么来代替 DataSource 或保留它?
编辑:
试过这个:
private void listBox1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Delete)
{
if (this.listBox1.SelectedIndex >= 0)
{
string obj = this.listBox1.SelectedValue.ToString();
data.Remove(obj);
listBox1.DataSource = null;
listBox1.DataSource = data;
}
}
}
但是当单击 Delete 键时,我在这里遇到错误:
private void listBox1_DrawItem(object sender, DrawItemEventArgs e)
{
string url = data[e.Index].Substring(0, 5);
using (Font f = new Font(FontFamily.GenericSansSerif, 8, FontStyle.Regular))
{
ColorText.ColorListBox(data, e);
}
}
在字符串 url 行:索引超出范围。必须是非负数且小于集合的大小
编辑:
我尝试使用标志:
private void listBox1_DrawItem(object sender, DrawItemEventArgs e)
{
if (deletedKey != true)
{
string url = data[e.Index].Substring(0, 5);
using (Font f = new Font(FontFamily.GenericSansSerif, 8, FontStyle.Regular))
{
ColorText.ColorListBox(data, e);
}
}
}
和:
private void listBox1_KeyDown(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Delete)
{
if (this.listBox1.SelectedIndex >= 0)
{
deletedKey = true;
string obj = this.listBox1.SelectedValue.ToString();
data.Remove(obj);
listBox1.DataSource = null;
listBox1.DataSource = data;
}
}
}
所以现在我没有收到错误,但它正在删除列表框中的所有项目我需要它来只删除现在/选定的一个即时消息。