PHP outputs formatted string function printf()
Example
Output a formatted string:
<?php
$number = 9;
$str = "Beijing";
printf("There are %u million bicycles in %s.",$number,$str);
?>Definition and usage
The printf() function outputs a formatted string.
arg1, arg2, ++ parameters will be inserted into the main string at the percent sign (%) symbol. This function is executed step by step. At the first % sign, insert arg1, at the second % sign, arg2, and so on.
Note: If there are more % symbols than arg arguments, you must use placeholders. The placeholder is inserted after the % symbol and consists of a number and "\$". See Example 2.
Tip: Related functions: sprintf(), vprintf(), vsprintf(), fprintf() and vfprintf()
Syntax
printf(format,arg1,arg2,arg++)
| Parameters | Description |
| format | Required. Specifies a string and how to format variables within it. Possible format values:
+ (Add + or - in front of a number to define the sign of the number. By default, only Negative numbers are marked, positive numbers are not marked)
|
| arg2 | |
| arg++ | |
技术细节 返回值： 返回被输出字符串的长度。 PHP 版本： 4+ 更多实例 实例 1 使用格式值 %f： <?php
$number = 123;
printf("%f",$number);
?>Copy after login 实例 2 使用占位符： <?php
$number = 123;
printf("With 2 decimals: %1$.2f
<br>With no decimals: %1$u",$number);
?>Copy after login 实例 3 所有可能的格式值的演示： <?php
$num1 = 123456789;
$num2 = -123456789;
$char = 50; // The ASCII Character 50 is 2
// Note: The format value "%%" returns a percent sign
printf("%%b = %b <br>",$num1); // Binary number
printf("%%c = %c <br>",$char); // The ASCII Character
printf("%%d = %d <br>",$num1); // Signed decimal number
printf("%%d = %d <br>",$num2); // Signed decimal number
printf("%%e = %e <br>",$num1); // Scientific notation (lowercase)
printf("%%E = %E <br>",$num1); // Scientific notation (uppercase)
printf("%%u = %u <br>",$num1); // Unsigned decimal number (positive)
printf("%%u = %u <br>",$num2); // Unsigned decimal number (negative)
printf("%%f = %f <br>",$num1); // Floating-point number (local settings aware)
printf("%%F = %F <br>",$num1); // Floating-point number (not local settings aware)
printf("%%g = %g <br>",$num1); // Shorter of %e and %f
printf("%%G = %G <br>",$num1); // Shorter of %E and %f
printf("%%o = %o <br>",$num1); // Octal number
printf("%%s = %s <br>",$num1); // String
printf("%%x = %x <br>",$num1); // Hexadecimal number (lowercase)
printf("%%X = %X <br>",$num1); // Hexadecimal number (uppercase)
printf("%%+d = %+d <br>",$num1); // Sign specifier (positive)
printf("%%+d = %+d <br>",$num2); // Sign specifier (negative)
?>Copy after login 实例 4 字符串说明符的演示： <?php
$str1 = "Hello";
$str2 = "Hello world!";
printf("[%s]<br>",$str1);
printf("[%8s]<br>",$str1);
printf("[%-8s]<br>",$str1);
printf("[%08s]<br>",$str1);
printf("[%'*8s]<br>",$str1);
printf("[%8.8s]<br>",$str2);
?>Copy after login printf()函数优点在于可以格式化输出! printf的格式控制的完整格式： % - 0 m.n l或h 格式字符 下面对组成格式说明的各项加以说明： ①%：表示格式说明的起始符号，不可缺少。 ②-：有-表示左对齐输出，如省略表示右对齐输出。 ③0：有0表示指定空位填0,如省略表示指定空位不填。 ④m.n：m指域宽，即对应的输出项在输出设备上所占的字符数。N指精度。用于说明输出的实型数的小数位数。为指定n时，隐含的精度为n=6位。 ⑤l或h:l对整型指long型，对实型指double型。h用于将整型的格式字符修正为short型。 The above is the detailed content of PHP outputs formatted string function printf(). For more information, please follow other related articles on the PHP Chinese website! Statement of this Website
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
Hot AI Tools
Undresser.AI UndressAI-powered app for creating realistic nude photos 
AI Clothes RemoverOnline AI tool for removing clothes from photos. 
Undress AI ToolUndress images for free 
Clothoff.ioAI clothes remover 
Video Face SwapSwap faces in any video effortlessly with our completely free AI face swap tool! 
Hot Article
Roblox: Grow A Garden - Complete Mutation Guide
3 weeks ago
By DDD
Roblox: Bubble Gum Simulator Infinity - How To Get And Use Royal Keys
3 weeks ago
By 尊渡假赌尊渡假赌尊渡假赌
How to fix KB5055612 fails to install in Windows 10?
3 weeks ago
By DDD
Nordhold: Fusion System, Explained
3 weeks ago
By 尊渡假赌尊渡假赌尊渡假赌
Mandragora: Whispers Of The Witch Tree - How To Unlock The Grappling Hook
3 weeks ago
By 尊渡假赌尊渡假赌尊渡假赌
Hot Tools
Notepad++7.3.1Easy-to-use and free code editor 
SublimeText3 Chinese versionChinese version, very easy to use 
Zend Studio 13.0.1Powerful PHP integrated development environment 
Dreamweaver CS6Visual web development tools 
SublimeText3 Mac versionGod-level code editing software (SublimeText3)
Hot Topics
Java Tutorial
1665
14
CakePHP Tutorial
1424
52
Laravel Tutorial
1322
25
PHP Tutorial
1270
29
C# Tutorial
1249
24
PHP and Python: Comparing Two Popular Programming Languages
Apr 14, 2025 am 12:13 AM
PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners. 
PHP in Action: Real-World Examples and Applications
Apr 14, 2025 am 12:19 AM
PHP is widely used in e-commerce, content management systems and API development. 1) E-commerce: used for shopping cart function and payment processing. 2) Content management system: used for dynamic content generation and user management. 3) API development: used for RESTful API development and API security. Through performance optimization and best practices, the efficiency and maintainability of PHP applications are improved. 
PHP: A Key Language for Web Development
Apr 13, 2025 am 12:08 AM
PHP is a scripting language widely used on the server side, especially suitable for web development. 1.PHP can embed HTML, process HTTP requests and responses, and supports a variety of databases. 2.PHP is used to generate dynamic web content, process form data, access databases, etc., with strong community support and open source resources. 3. PHP is an interpreted language, and the execution process includes lexical analysis, grammatical analysis, compilation and execution. 4.PHP can be combined with MySQL for advanced applications such as user registration systems. 5. When debugging PHP, you can use functions such as error_reporting() and var_dump(). 6. Optimize PHP code to use caching mechanisms, optimize database queries and use built-in functions. 7 
PHP vs. Python: Understanding the Differences
Apr 11, 2025 am 12:15 AM
PHP and Python each have their own advantages, and the choice should be based on project requirements. 1.PHP is suitable for web development, with simple syntax and high execution efficiency. 2. Python is suitable for data science and machine learning, with concise syntax and rich libraries. 
The Enduring Relevance of PHP: Is It Still Alive?
Apr 14, 2025 am 12:12 AM
PHP is still dynamic and still occupies an important position in the field of modern programming. 1) PHP's simplicity and powerful community support make it widely used in web development; 2) Its flexibility and stability make it outstanding in handling web forms, database operations and file processing; 3) PHP is constantly evolving and optimizing, suitable for beginners and experienced developers. 
PHP and Python: Code Examples and Comparison
Apr 15, 2025 am 12:07 AM
PHP and Python have their own advantages and disadvantages, and the choice depends on project needs and personal preferences. 1.PHP is suitable for rapid development and maintenance of large-scale web applications. 2. Python dominates the field of data science and machine learning. 
PHP vs. Other Languages: A Comparison
Apr 13, 2025 am 12:19 AM
PHP is suitable for web development, especially in rapid development and processing dynamic content, but is not good at data science and enterprise-level applications. Compared with Python, PHP has more advantages in web development, but is not as good as Python in the field of data science; compared with Java, PHP performs worse in enterprise-level applications, but is more flexible in web development; compared with JavaScript, PHP is more concise in back-end development, but is not as good as JavaScript in front-end development. 
PHP and Python: Different Paradigms Explained
Apr 18, 2025 am 12:26 AM
PHP is mainly procedural programming, but also supports object-oriented programming (OOP); Python supports a variety of paradigms, including OOP, functional and procedural programming. PHP is suitable for web development, and Python is suitable for a variety of applications such as data analysis and machine learning. 
|
