debug_backtrace

debug_backtrace — 产生一条回溯跟踪(backtrace)

debug_backtrace ([ int $options = DEBUG_BACKTRACE_PROVIDE_OBJECT [, int $limit = 0 ]] ) : array

options

limit
用于限制返回堆栈帧的数量。 默认为 (limit=0) ，返回所有的堆栈帧。

debug_backtrace() - show all options
debug_backtrace(0) - exlude ["object"]
debug_backtrace(1) - same as debug_backtrace()
debug_backtrace(2) - exlude ["object"] AND ["args"]

<?php
    public function dump( $var ) {
        $result = var_export( $var, true );
        $loc = $this->whereCalled();
        return "\n<pre>Dump: $loc\n$result</pre>";
    }

    public function whereCalled( $level = 1 ) {
        $trace = debug_backtrace();
        $file   = $trace[$level]['file'];
        $line   = $trace[$level]['line'];
        $object = $trace[$level]['object'];
        if (is_object($object)) { $object = get_class($object); }

        return "Where called: line $line of $object \n(in $file)";
    }