Find index of character in string
The following asp.net c# example code demonstrate us how can we find
index of a specified character in a stringprogrammatically at run time
in an asp.net application. .Net framework's String Class represent Text as a
series of UnicodeCharacters.
String Class String.IndexOf(Char) overloaded method reports the zero-based index of the first occurrence of the specified Unicode characterin this string. String.IndexOf(Char) method has a required parameter named 'value' which data type is System.Char. This parameter valuerepresent a Unicode character to seek.
String.IndexOf(Char) method return a System.Int32 data type integer value. This return value represent the zero-based index position ofspecified character, if that character is found; otherwise it return -1.
So, we can find index of a character from a string using String.IndexOf(Char) method. We just need to call the method andspecify the string instance and a character to search.
String Class String.IndexOf(Char) overloaded method reports the zero-based index of the first occurrence of the specified Unicode characterin this string. String.IndexOf(Char) method has a required parameter named 'value' which data type is System.Char. This parameter valuerepresent a Unicode character to seek.
String.IndexOf(Char) method return a System.Int32 data type integer value. This return value represent the zero-based index position ofspecified character, if that character is found; otherwise it return -1.
So, we can find index of a character from a string using String.IndexOf(Char) method. We just need to call the method andspecify the string instance and a character to search.
find-index-of-character-in-string.aspx
<%@ Page Language="C#" AutoEventWireup="true"%>
<!DOCTYPE html>
<script runat="server">
protected void Button1_Click(object sender, System.EventArgs e)
{
//this section create a string variable.
string plants = "Damask Violet. Violet Bloom. Western Redbud. Walnut.";
Label1.Text = "string of plants..................<br />";
Label1.Text += plants+"<br />";
//character to find/search index in string.
char indexOfCharcterToFind = 'V';
//this line find/search first index of a character in string
if (plants.IndexOf(indexOfCharcterToFind) != -1)
{
Label1.Text += "<br />character[V] found in string. first index of: ";
Label1.Text += plants.IndexOf(indexOfCharcterToFind);
}
else
{
Label1.Text += "<br />character [V] not found in string";
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>c# example - find index of character in string</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<h2 style="color:MidnightBlue; font-style:italic;">
c# example - find index of character in string
</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="find index of character in string"
OnClick="Button1_Click"
Height="40"
Font-Bold="true"
/>
</div>
</form>
</body>
</html>
