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How to use the PHP function count() to find the length of an array_PHP Tutorial
- WBOYOriginal
- 2016-07-15 13:29:361126browse
New Learningint count (mixed var)
Returns the number of cells in var, usually an array (any other type has only one cell).
If var is not an array type, 1 will be returned (exception: the result of count(NULL) is 0).
Warning
The PHP function count() returns 0 for uninitialized variables, but also returns 0 for empty arrays. Use isset() to test whether a variable has been initialized.
Example 1. count() example
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<span><strong><font color="#006699"><span class="tag"><?</SPAN><SPAN class=tag-name>php</SPAN></FONT></STRONG><SPAN> </SPAN></SPAN><LI class=""><SPAN>$vegetables[0] = "corn"; </SPAN><LI class=alt><SPAN>$vegetables[1] = "broccoli"; </SPAN><LI class=""><SPAN>$vegetables[2] = "zucchini"; </SPAN><LI class=alt><SPAN>$</SPAN><SPAN class=attribute><FONT color=#ff0000>text</FONT></SPAN><SPAN> = </SPAN><SPAN class=attribute-value><FONT color=#0000ff>implode</FONT></SPAN><SPAN>(",", $vegetables); </SPAN></SPAN><LI class=""><SPAN>echo $text; </SPAN><LI class=alt><SPAN></SPAN><SPAN class=tag><STRONG><FONT color=#006699>?></span></font></strong></span><span> </span><span></span>
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Sometimes if you don’t know the PHP function count(), use the stupid method: select count(*) from table
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