极客笔记PHP fprint() 函数
PHP fprint() 函数用于向流中写入格式化的字符串。换句话说，我们可以说这个函数将字符串格式化到指定的输出流（文件或数据库）中。
语法
fprintf(stream,format,arg1,arg2,arg++)
| 参数 | 描述 | 必需/可选 |
|---|---|---|
| stream | 指定要写入/输出字符串的位置 | 必需 |
| Format | 指定字符串。 | 必需 |
| arg1 | 指定要插入的第一个参数。 | 必需 |
| arg2 | 指定要插入的第二个参数。 | 可选 |
| arg++ | 指定要插入的第三个、第四个等参数。 | 可选 |
示例1
<?php
number = 9;str = "javatpoint";
file = fopen("test.txt","w");
echo fprintf(file,"There are %u million bicycles in %s.",number,str);
?>
输出:
43
示例2
<?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)
?>
输出：
%b = 111010110111100110100010101
%c = 2
%d = 123456789
%d = -123456789
%e = 1.234568e+8
%E = 1.234568E+8
示例3
<?php
num1 = 123456789;num2 = -123456789;
char = 50; // The ASCII Character 50 is 2
// Note: The format value "%%" returns a percent sign
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
?>
输出：
%u = 123456789
%u = 4171510507
%f = 123456789.000000
%F = 123456789.000000
%g = 1.23457e+8
%G = 1.23457E+8
%o = 726746425
示例4
<?php
num1 = 123456789;num2 = -123456789;
char = 50; // The ASCII Character 50 is 2
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)*/
?>
输出：
%s = 123456789
%x = 75bcd15
%X = 75BCD15
%+d = +123456789
%+d = -123456789