How to use C# string Insert

The Insert() function within the String Class assumes a pivotal role by providing a mechanism to insert a string at a specified index within an existing String instance. This function enables developers to precisely position and incorporate additional textual content within a string, expanding its length and modifying its overall structure.

When the Insert() function is invoked, it initiates a deliberate process of inserting the specified string at the designated index within the existing String instance. This insertion operation meticulously adjusts the position of characters within the string, accommodating the new content seamlessly and ensuring the preservation of the original characters' order and integrity.

string string.Insert(int ind,string str)
  1. ind - The index of the specified string to be inserted.
  2. str - The string to be inserted.
  1. String - The result string.
  1. System.ArgumentOutOfRangeException: startIndex is negative or greater than the length of this instance.
  2. System.ArgumentNullException : If the argument is null.


"This is Test".Insert(8,"Insert ") returns "This is Insert Test"

C# insert() function

The Insert() function empowers developers to manipulate and modify strings with precision and control, catering to specific requirements and objectives. By employing this function, programmers can confidently craft dynamic and flexible string representations, enhancing the adaptability and versatility of their codebase.

Full Source C#
using System; using System.Windows.Forms; namespace WindowsApplication1 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void button1_Click(object sender, EventArgs e) { string str = "This is CSharp Test"; string insStr = "Insert "; string strRes = str.Insert(15, insStr); MessageBox.Show(strRes); } } }

When you execute this C# program you will get the message box showing "This is CSharp Insert Test"


The C# Insert() function within the String Class offers developers a robust tool to insert a specified string at a designated index within an existing string instance. This capability enables precise text positioning, facilitating the creation of dynamic and adaptable string structures within the C# programming paradigm.