The task is to detect the changes in the textbox content with JavaScript. There are some common approaches that are discussed below.
Approach 1: We will use the onchange event in the input element and call a function to see the effect.
Example: In this example, we are using the above explained-approach.
html
<!DOCTYPE html><html><head> <title> Detect If Textbox content has changed using pure JavaScript </title></head><body style="text-align:center;"> <h1 style="color:green;"> neveropen </h1> <p> Change the text of input text and click outside of it to see. </p> <input id="input" name="input" onchange="GFG_Fun()" /> <br> <br> <script> function GFG_Fun() { alert('Changed'); } </script></body></html> |
Output:
Approach 2: There are few other events that can be used to detect the change in content of textbox. Use any or all of them onchange event, onpropertychange event, onkeyup event, onpaste event and oninput event in the input element and call a function to see the effect.
Example: In this example, we are implementing the above approach.
html
<!DOCTYPE html><html><head> <title> Detect If Textbox content has changed using pure JavaScript </title></head><body style="text-align:center;"> <h1 style="color:green;"> neveropen </h1> <p> Change the text of input text and click outside of it to see. </p> <input id="input" name="input" onchange onpropertychange onkeyuponpaste oninput="GFG_Fun()" /> <br> <br> <script> function GFG_Fun() { alert('Changed'); } </script></body></html> |
Output:
Approach 3: Using addEventListener() method: In javascript with the help of the addEventListener() method, we can attach the input javascript event to the textarea.
Example: In this example, we are using the above-explained approach.
HTML
<!DOCTYPE html><html lang="en"><head> <style> h1 { text-align: center; } .abc { display: flex; justify-content: center; text-align: center; } </style></head><body> <h1 style="color:green;"> neveropen </h1> <div class="abc"> <input id="gfg"> </div> <script> document.getElementById("gfg") .addEventListener("input", (event) => alert("Changed!")); </script></body></html> |
Output:
