FAQ: How do I pad a string with blanks or pad a number with zeroes? 
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 FAQ: How do I pad a string with blanks or pad a number with zeroes?

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+
  How do I pad a string with blanks or pad a number with zeroes?

    (This answer contributed by Uri Guttman, with kibitzing from Bart
    Lateur.)

    In the following examples, "$pad_len" is the length to which you wish to
    pad the string, "$text" or "$num" contains the string to be padded, and
    "$pad_char" contains the padding character. You can use a single
    character string constant instead of the "$pad_char" variable if you
    know what it is in advance. And in the same way you can use an integer
    in place of "$pad_len" if you know the pad length in advance.

    The simplest method uses the "sprintf" function. It can pad on the left
    or right with blanks and on the left with zeroes and it will not
    truncate the result. The "pack" function can only pad strings on the
    right with blanks and it will truncate the result to a maximum length of
    "$pad_len".

        # Left padding a string with blanks (no truncation):
        $padded = sprintf("%${pad_len}s", $text);

        # Right padding a string with blanks (no truncation):
        $padded = sprintf("%-${pad_len}s", $text);

        # Left padding a number with 0 (no truncation):
        $padded = sprintf("%0${pad_len}d", $num);

        # Right padding a string with blanks using pack (will truncate):
        $padded = pack("A$pad_len",$text);

    If you need to pad with a character other than blank or zero you can use
    one of the following methods. They all generate a pad string with the
    "x" operator and combine that with "$text". These methods do not
    truncate "$text".

    Left and right padding with any character, creating a new string:

        $padded = $pad_char x ( $pad_len - length( $text ) ) . $text;
        $padded = $text . $pad_char x ( $pad_len - length( $text ) );

    Left and right padding with any character, modifying "$text" directly:

        substr( $text, 0, 0 ) = $pad_char x ( $pad_len - length( $text ) );
        $text .= $pad_char x ( $pad_len - length( $text ) );

-

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Tue, 02 Mar 2004 01:16:59 GMT  
 
 [ 1 post ] 

 Relevant Pages 

1. FAQ 4.33 How do I pad a string with blanks or pad a number with zeroes?

2. FAQ 4.33 How do I pad a string with blanks or pad a number with zeroes?

3. FAQ 4.33 How do I pad a string with blanks or pad a number with zeroes?

4. FAQ 4.33 How do I pad a string with blanks or pad a number with zeroes?

5. FAQ 4.33 How do I pad a string with blanks or pad a number with zeroes?

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