Blog : PHP substr_replace() Function

PHP substr_replace() Function

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 Complete PHP String Reference
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Definition and Usage
The substr_replace() function replaces a part of a string with another string.

Syntax
substr_replace(string,replacement,start,length)  

Parameter Description
string Required. Specifies the string to check
replacement Required. Specifies the string to insert
start Required. Specifies where to start replacing in the string
A positive number - Start replacing at the specified position in the string
Negative number - Start replacing at the specified position from the end of the string
0 - Start replacing at the first character in the string
 
length Optional. Specifies how many characters should be replaced. Default is the same length as the string.
A positive number - The length of string to be replaced
A negative number - How many characters should be left at end of string after replacing
0 - Insert instead of replace
 


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Tips and Notes
Note: If start is a negative number and length is less than or equal to start, length becomes 0.


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Example
echo substr_replace("Hello world","earth",6);
?>  

The output of the code above will be:

Hello earth