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substr() Function Returns part of string. Returns the extracted part of the string, returns FALSE if it fails, or returns an empty string.
Note: If the start parameter is a negative number and length is less than or equal to start, then length is 0.
The substr function in PHP is defined as follows:
substr(string,start,length)
The parameter description is as follows:
| Parameter | Description |
|---|---|
| string | Required. Specifies a part of the string to be returned. |
| start |
Required. Specifies where in the string to begin.
|
| length |
Optional. Specifies the length of the returned string. The default is until the end of the string.
|
";
echo substr("Welcome to www.jb51.net!",4,14); //从第4个字符开始连续截取14个字符
echo "
";
echo substr("Welcome to www.jb51.net!",-4,4); //从倒数第4个开始截取4个字符
echo "
";
echo substr("Welcome to www.jb51.net!",0,-4); //从第一个字符开始截取,截取到倒数第4个字符
?>The running result is as follows:Welcome to www.jb51.net! ome to www.jb5 net! Welcome to www.jb51.
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