Dictionary remove by condition
dictionary-remove-where.aspx
<%@ Page Language="C#" AutoEventWireup="true"%>
<!DOCTYPE html>
<script runat="server">
protected void Button1_Click(object sender, System.EventArgs e)
{
//initialize a dictionary with keys and values.
Dictionary<int, string> birds = new Dictionary<int, string>() {
{1,"Squirrel Cuckoo"},
{2,"Golden Oriole"},
{3,"Golden Nightjar"},
{4,"Northern Oriole"},
{5,"Warbling Vireo"}
};
Label1.Text = "dictionary keys and values..........";
foreach (KeyValuePair<int, string> pair in birds)
{
Label1.Text += "<br />" + pair.Key + " ........ " + pair.Value;
}
int[] keysToDelete = birds.Where(x => x.Value.EndsWith("Oriole")).Select(x => x.Key).ToArray();
//another condition to remove dictionary elements.
//int[] keysToDelete = birds.Keys.Where(x => x < 3).ToArray();
Label1.Text += "<br /><br />removing elements from dictionary<br />";
foreach (int key in keysToDelete)
{
birds.Remove(key);
Label1.Text += "key [" + key + "] removed from dictionary<br />";
}
Label1.Text += "<br />elemetns removed which value ends with [Oriole]..........";
Label1.Text += "<br />dictionary keys and values after remove..........";
foreach (KeyValuePair<int, string> pair in birds)
{
Label1.Text += "<br />" + pair.Key + " ........ " + pair.Value;
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>c# example - dictionary remove where</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<h2 style="color:MidnightBlue; font-style:italic;">
c# example - dictionary remove where
</h2>
<hr width="550" align="left" color="Gainsboro" />
<asp:Label
ID="Label1"
runat="server"
Font-Size="Large"
>
</asp:Label>
<br /><br />
<asp:Button
ID="Button1"
runat="server"
Text="dictionary remove where"
OnClick="Button1_Click"
Height="40"
Font-Bold="true"
/>
</div>
</form>
</body>
</html>

- How to use KeyValuePair in a Dictionary
- Best way to iterate over a Dictionary
- How to iterate over a Dictionary using foreach loop
- How to initialize a Dictionary
- How to sort a Dictionary by key
- How to sort a Dictionary by value
- How to remove range of items from a Dictionary
- How to get a range of items from a Dictionary
- How to remove an item from Dictionary by value
- How to convert a Dictionary to a string