Three ways to output the results of running a javascript script.
JavaScript is one of the important languages in web development. It is widely used in front-end interaction, back-end data processing and browser plug-ins. During the development process, we usually need to output the results of script execution for debugging or verification. This article will introduce three methods of outputting JavaScript script execution results.
1. Use alert()
The alert window is one of the most common output methods in JavaScript. It can create a pop-up window that displays the specified string, as shown below:
alert("Hello, World!");
alert() accepts a string parameter and displays it in the browser when executed. It is usually used for simple testing or debugging.
2. Use console.log()
console.log() is one of the most commonly used commands for debugging JavaScript. It can output any type of data, such as strings, objects, or arrays. , as shown below: The output of
console.log("Hello, World!");
console.log() is displayed in the browser console, which can help us analyze the debugger more conveniently. Normally, during the development process, we will output a large amount of debugging information to the console in order to view the program flow and value changes in real time.
3. Use document.write()
document.write() to write HTML code or plain text in the specified document, as shown below:
document.write("Hello, World!");
It The string "Hello, World!" will be output in the current page. However, it should be noted that if the document.write() method is executed after the document is loaded, the existing document content will be overwritten. In actual development, we should avoid using the document.write() method to avoid unexpected behavior.
Summary
The above are the three methods for JavaScript to output script running results. Using alert(), console.log() and document.write() methods can help us observe and write more easily. Debugger. In actual development, we should pay attention to using these methods to improve development efficiency, and delete output statements after development is completed to avoid excessive impact on performance.
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