Use the PHP function "str_pad" to pad the left or right side of a string with a specified string

Use the PHP function "str_pad" to fill the left or right side of the string with the specified string

When writing PHP code, we often need to process strings. Sometimes, we need to pad a string to a specified length. In this case, we can use PHP's built-in function "str_pad" to complete this task. The "str_pad" function pads a specified string on the left or right side of the string to a specified length.

The basic syntax of the "str_pad" function is as follows:

string str_pad ( string $input , int $pad_length [, string $pad_string = " " [, int $pad_type = STR_PAD_RIGHT ]] )

Among them, the parameter $input is the string to be filled, $pad_length is the length of the filled string, $pad_string is the string used to fill, and $pad_type specifies the direction and position of filling.

The following are some examples of using the "str_pad" function:

1. Fill the specified string on the right side of the string:

$input = "Hello";
$pad_length = 10;
$pad_string = "World";
$pad_type = STR_PAD_RIGHT;
$result = str_pad($input, $pad_length, $pad_string, $pad_type);

//The output result is "HelloWorld"

In this example, the length of the string "Hello" is 5, and the specified padding length is 10. Since the padding direction is specified as right padding, the function pads the right side of the string with "World" until the specified length is reached.

2. Fill the specified string on the left side of the string:

$input = "Hello";
$pad_length = 10;
$pad_string = "World";
$pad_type = STR_PAD_LEFT;
$result = str_pad($input, $pad_length, $pad_string, $pad_type);

//The output result is "WorldHello"

In this In the example, the length of the string "Hello" is 5, and the specified padding length is 10. Since the padding direction is specified as left padding, the function pads the left side of the string with "World" until the specified length is reached.

3. Pad the specified string on both sides of the string:

$input = "Hello";
$pad_length = 9;
$pad_string = "World";
$pad_type = STR_PAD_BOTH;
$result = str_pad($input, $pad_length, $pad_string, $pad_type);

// The output result is "WorldHelloWorld"

In this In the example, the length of the string "Hello" is 5, and the specified padding length is 9. Because the padding direction is specified as padding on both sides, the function will distribute "World" evenly on both sides of the string until the specified length is reached.

The above are some basic usage examples of the PHP function "str_pad". We can apply this function flexibly as needed to ensure that the string reaches the length we expect. Whether for string alignment, generating canonical text formats, or other string processing scenarios, "str_pad" is a very useful function.

Summary:

This article introduces the usage and examples of the PHP function "str_pad". We can easily pad a string to a specified length by inserting the specified string on the left or right side of the string using the "str_pad" function. This function is very useful in string processing and can be applied to a variety of scenarios to provide better string processing and formatting functions. It should be emphasized that by carefully setting the "pad_length" and "pad_string" parameters, we can flexibly adjust the position and content of the padding to meet our needs.

I hope this article can be helpful to everyone in using PHP string processing!

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