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php 打印、显示、输出函数收集_PHP教程

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Jul 13, 2016 pm 05:37 PM

echophpthisworld函数打印收集显示输出

<span style="color: rgb(0,0,0)"><font face="NSimsun"><span style="color: rgb(0,0,187)"><?php <br />
</span><span style="color: rgb(0,119,0)">echo </span><span style="color: rgb(221,0,0)">"Hello World"</span></font><span style="color: rgb(0,119,0)"><font face="NSimsun">;<br>
<br>
echo </font></span><span style="color: rgb(221,0,0)"><font face="NSimsun">"This spans<br>
multiple lines. The newlines will be<br>
output as well"</font></span><font face="NSimsun"><span style="color: rgb(0,119,0)">;<br>
<br>
echo </span><span style="color: rgb(221,0,0)">"This spans
multiple lines. The newlines will be
output as well."</span></font><font face="NSimsun"><span style="color: rgb(0,119,0)">;<br>
<br>
echo </span><span style="color: rgb(221,0,0)">"Escaping characters is done "Like this"."</span></font><span style="color: rgb(0,119,0)"><font face="NSimsun">;<br>
<br>
</font></span><font face="NSimsun"><span style="color: rgb(255,128,0)">// You can use variables inside of an echo statement<br>
</span><span style="color: rgb(0,0,187)">$foo </span><span style="color: rgb(0,119,0)">= </span><span style="color: rgb(221,0,0)">"foobar"</span></font><font face="NSimsun"><span style="color: rgb(0,119,0)">;<br>
</span><span style="color: rgb(0,0,187)">$bar </span><span style="color: rgb(0,119,0)">= </span><span style="color: rgb(221,0,0)">"barbaz"</span></font><font face="NSimsun"><span style="color: rgb(0,119,0)">;<br>
<br>
echo </span><span style="color: rgb(221,0,0)">"foo is </span><span style="color: rgb(0,0,187)">$foo</span><span style="color: rgb(221,0,0)">"</span><span style="color: rgb(0,119,0)">; </span></font><font face="NSimsun"><span style="color: rgb(255,128,0)">// foo is foobar<br>
<br>
// You can also use arrays<br>
</span><span style="color: rgb(0,0,187)">$baz </span><span style="color: rgb(0,119,0)">= array(</span><span style="color: rgb(221,0,0)">"value" </span><span style="color: rgb(0,119,0)">=> </span><span style="color: rgb(221,0,0)">"foo"</span></font><font face="NSimsun"><span style="color: rgb(0,119,0)">);<br>
<br>
echo </span><span style="color: rgb(221,0,0)">"this is </span><span style="color: rgb(0,119,0)">{</span><span style="color: rgb(0,0,187)">$baz</span><span style="color: rgb(0,119,0)">[</span><span style="color: rgb(221,0,0)">value</span><span style="color: rgb(0,119,0)">]}</span><span style="color: rgb(221,0,0)"> !"</span><span style="color: rgb(0,119,0)">; </span></font><font face="NSimsun"><span style="color: rgb(255,128,0)">// this is foo !<br>
<br>
// Using single quotes will print the variable name, not the value<br>
</span><span style="color: rgb(0,119,0)">echo </span><span style="color: rgb(221,0,0)">foo is $foo</span><span style="color: rgb(0,119,0)">; </span></font><font face="NSimsun"><span style="color: rgb(255,128,0)">// foo is $foo<br>
<br>
// If you are not using any other characters, you can just echo variables<br>
</span><span style="color: rgb(0,119,0)">echo </span><span style="color: rgb(0,0,187)">$foo</span><span style="color: rgb(0,119,0)">;          </span></font><font face="NSimsun"><span style="color: rgb(255,128,0)">// foobar<br>
</span><span style="color: rgb(0,119,0)">echo </span><span style="color: rgb(0,0,187)">$foo</span><span style="color: rgb(0,119,0)">,</span><span style="color: rgb(0,0,187)">$bar</span><span style="color: rgb(0,119,0)">;     </span></font><font face="NSimsun"><span style="color: rgb(255,128,0)">// foobarbarbaz<br>
<br>
// Some people prefer passing multiple parameters to echo over concatenation.<br>
</span><span style="color: rgb(0,119,0)">echo </span><span style="color: rgb(221,0,0)">This </span><span style="color: rgb(0,119,0)">, </span><span style="color: rgb(221,0,0)">string </span><span style="color: rgb(0,119,0)">, </span><span style="color: rgb(221,0,0)">was </span><span style="color: rgb(0,119,0)">, </span><span style="color: rgb(221,0,0)">made </span><span style="color: rgb(0,119,0)">, </span><span style="color: rgb(221,0,0)">with multiple parameters.</span><span style="color: rgb(0,119,0)">, </span><span style="color: rgb(0,0,187)">chr</span><span style="color: rgb(0,119,0)">(</span><span style="color: rgb(0,0,187)">10</span></font><font face="NSimsun"><span style="color: rgb(0,119,0)">);<br>
echo </span><span style="color: rgb(221,0,0)">This  </span><span style="color: rgb(0,119,0)">. </span><span style="color: rgb(221,0,0)">string  </span><span style="color: rgb(0,119,0)">. </span><span style="color: rgb(221,0,0)">was  </span><span style="color: rgb(0,119,0)">. </span><span style="color: rgb(221,0,0)">made  </span><span style="color: rgb(0,119,0)">. </span><span style="color: rgb(221,0,0)">with concatenation. </span><span style="color: rgb(0,119,0)">. </span><span style="color: rgb(221,0,0)">"
"</span></font><span style="color: rgb(0,119,0)"><font face="NSimsun">;<br>
<br>
echo 
</font></span><font face="NSimsun"><span style="color: rgb(221,0,0)">This uses the "here document" syntax to output<br>
multiple lines with </span><span style="color: rgb(0,0,187)">$variable</span></font><span style="color: rgb(221,0,0)"><font face="NSimsun"> interpolation. Note<br>
that the here document terminator must appear on a<br>
line with just a semicolon. no extra whitespace!<br>
</font></span><span style="color: rgb(0,119,0)"><font face="NSimsun">END;<br>
<br>
</font></span><font face="NSimsun"><span style="color: rgb(255,128,0)">// Because echo does not behave like a function, the following code is invalid.<br>
</span><span style="color: rgb(0,119,0)">(</span><span style="color: rgb(0,0,187)">$some_var</span><span style="color: rgb(0,119,0)">) ? echo </span><span style="color: rgb(221,0,0)">true </span><span style="color: rgb(0,119,0)">: echo </span><span style="color: rgb(221,0,0)">false</span></font><span style="color: rgb(0,119,0)"><font face="NSimsun">;<br>
<br>
</font></span><font face="NSimsun"><span style="color: rgb(255,128,0)">// However, the following examples will work:<br>
</span><span style="color: rgb(0,119,0)">(</span><span style="color: rgb(0,0,187)">$some_var</span><span style="color: rgb(0,119,0)">) ? print </span><span style="color: rgb(221,0,0)">true </span><span style="color: rgb(0,119,0)">: print </span><span style="color: rgb(221,0,0)">false</span><span style="color: rgb(0,119,0)">; </span></font><font face="NSimsun"><span style="color: rgb(255,128,0)">// print is also a construct, but<br>
                                             // it behaves like a function, so<br>
                                             // it may be used in this context.<br>
</span><span style="color: rgb(0,119,0)">echo </span><span style="color: rgb(0,0,187)">$some_var </span><span style="color: rgb(0,119,0)">? </span><span style="color: rgb(221,0,0)">true</span><span style="color: rgb(0,119,0)">: </span><span style="color: rgb(221,0,0)">false</span><span style="color: rgb(0,119,0)">; </span></font><font face="NSimsun"><span style="color: rgb(255,128,0)">// changing the statement around<br>
</span><span style="color: rgb(0,0,187)">?></span> </font></span>

====================
PHP die() 函数

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