How to use prompt in js

The prompt() method in JavaScript is used to display a dialog box with an input prompt box to the user, wait for user input and return the input value, or return null if the user cancels or closes. 1. Syntax: prompt([message]); 2. Parameter: message (optional, prompt information); 3. Return value: user input value (string), or null if canceled; 4. Note: a. The input value is always a string; b. Will hang script execution; c. Use with caution to obtain sensitive information; d. May be restricted on mobile devices.

How to use the prompt() method in JavaScript

The prompt() method is used in JavaScript to notify the user Displays a dialog box with an input prompt box and waits for user input. It returns the value entered by the user, or null if the user clicks Cancel or closes the dialog box.

Syntax

<code class="js">prompt([message]);</code>

Parameters

• message: Optional. Prompt message displayed in the dialog box.

Return Value

• A string representing the value entered by the user, or null if the user clicks Cancel or closes the dialog box .

Example

The following example displays a prompt() dialog box with a prompt message and prints the content entered by the user:

<code class="js">const name = prompt("请输入你的名字：");
console.log(name);</code>

Notes

• String conversion: prompt() method always returns the input value as a string, even if the input value is a number or Boolean value. If needed, you can use the parseInt() or parseFloat() functions to convert it to the appropriate type.
• User interaction: The prompt() method will suspend script execution until the user enters a value or cancels the dialog box.
• Security considerations: The prompt() method should not be used to obtain sensitive information, because any code with access to the user's browser can read the entered value.
• Mobile devices: On mobile devices, prompt() popups may conflict with other applications or be blocked. It is recommended to use alternatives on mobile devices, such as modal dialogs or the alert() method.

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