(PHP 5 >= 5.1.0, PHP 7)
SplFileObject::fscanf — フォーマットに従ってファイルからの入力をパースする
ファイルから 1 行読み込み、sprintf() のドキュメントで説明される規定の format
に従って解釈されます。
format
文字列のホワイトスペースはファイルからの行のホワイトスペースとマッチします。このことが意味するのはフォーマット文字列のタブ (\t) でさえも入力ストリームの 1 つのスペース文字とマッチしてしまうということです。
format
The format string is composed of zero or more directives: ordinary characters (excluding %) that are copied directly to the result and conversion specifications, each of which results in fetching its own parameter.
A conversion specification follows this prototype: %[flags][width][.precision]specifier.
Flag | 説明 |
---|---|
- | Left-justify within the given field width; Right justification is the default |
+ | Prefix positive numbers with a plus sign +; Default only negative are prefixed with a negative sign. |
(space) | Pads the result with spaces. This is the default. |
0 | Only left-pads numbers with zeros. With s specifiers this can also right-pad with zeros. |
'(char) | Pads the result with the character (char). |
An integer that says how many characters (minimum) this conversion should result in.
A period . followed by an integer who's meaning depends on the specifier:
注意: If the period is specified without an explicit value for precision, 0 is assumed.
注意: Attempting to use a position specifier greater than
PHP_INT_MAX
will generate warnings.
Specifier | 説明 |
---|---|
% | A literal percent character. No argument is required. |
b | The argument is treated as an integer and presented as a binary number. |
c | The argument is treated as an integer and presented as the character with that ASCII. |
d | The argument is treated as an integer and presented as a (signed) decimal number. |
e | The argument is treated as scientific notation (e.g. 1.2e+2). The precision specifier stands for the number of digits after the decimal point since PHP 5.2.1. In earlier versions, it was taken as number of significant digits (one less). |
E | Like the e specifier but uses uppercase letter (e.g. 1.2E+2). |
f | The argument is treated as a float and presented as a floating-point number (locale aware). |
F | The argument is treated as a float and presented as a floating-point number (non-locale aware). Available as of PHP 5.0.3. |
g |
General format. Let P equal the precision if nonzero, 6 if the precision is omitted, or 1 if the precision is zero. Then, if a conversion with style E would have an exponent of X: If P > X ≥ −4, the conversion is with style f and precision P − (X + 1). Otherwise, the conversion is with style e and precision P − 1. |
G | Like the g specifier but uses E and F. |
o | The argument is treated as an integer and presented as an octal number. |
s | The argument is treated and presented as a string. |
u | The argument is treated as an integer and presented as an unsigned decimal number. |
x | The argument is treated as an integer and presented as a hexadecimal number (with lowercase letters). |
X | The argument is treated as an integer and presented as a hexadecimal number (with uppercase letters). |
The c type specifier ignores padding and width
Attempting to use a combination of the string and width specifiers with character sets that require more than one byte per character may result in unexpected results
Variables will be co-erced to a suitable type for the specifier:
Type | Specifiers |
---|---|
string | s |
integer | d, u, c, o, x, X, b |
double | g, G, e, E, f, F |
...
オプションの割り当て値。
このメソッドに渡される引数がひとつしかない場合、処理される値は配列として返されます。そうでなければ、オプションパラメータが渡される場合、メソッドは割り当て値の個数を返します。オプションパラメータは参照渡しでなければなりません。
例1 SplFileObject::fscanf() の例
<?php
$file = new SplFileObject("misc.txt");
while ($userinfo = $file->fscanf("%s %s %s")) {
list ($name, $profession, $countrycode) = $userinfo;
// $name $profession $countrycode で何かを行う
}
?>
users.txt の内容
javier argonaut pe hiroshi sculptor jp robert slacker us luigi florist it