php 从php中的函数返回变量（返回不起作用）
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Returning a variable from a function in php (return not working)
提问by pedalpete
I'm building an XML page inside of a function, and for some strange reason I don't get the whole thing spit out of the function. I've tried
我正在一个函数内构建一个 XML 页面，但出于某种奇怪的原因，我没有从函数中吐出全部内容。我试过了
return $thisXml;
}
echo $thisXML;
and I only get the xml declaration which is in the variable before the function. If i put an echo in the function, i get everything back as I should.
我只得到函数之前变量中的 xml 声明。如果我在函数中放置一个回声，我会按我应该的方式返回所有内容。
my page essentially looks like this
我的页面基本上是这样的
$thisXml = 'xml declaration stuff';
function getThisXML($thisXML){
for(i=1; i<5; i++){
$query "has the 5 in it";
while ($mysqlQuery =mysql_fetch_array($theQuery) {
$thisXml.='add the xml';
}
$thisXml.='close the last element';
return $thisXml;
}
echo $thisXml;
as i said, if I replace the 'return' with 'echo', I get all the nice xml. if I echo outside the function, I only get the original declaration.
正如我所说，如果我用“回声”替换“返回”，我会得到所有漂亮的 xml。如果我在函数外回显，我只会得到原始声明。
really strange, and i've been struggling with this one all day.
真的很奇怪，我一整天都在为这个而苦苦挣扎。
回答by Steerpike
return $thisXml;
}
echo $thisXML;
$thisXML; only exists in the scope of the function.
Either make $thisXML; global (bad idea) or echo getThisXML()where getThisXML is the function that returns $thisXML;
$thisXML; 只存在于函数范围内。要么制作 $thisXML; 全局（坏主意）或echo getThisXML()getThisXML 是返回函数的地方$thisXML；
回答by jeroen
Are you actually calling the function in the sense of:
您实际上是在以下意义上调用该函数：
$thisXml = getThisXML($someinput);
Maybe a silly question, but I don′t see it in your description.
也许是一个愚蠢的问题，但我在你的描述中没有看到。
回答by Matias
You need to invoke the function!
您需要调用该函数！
$thisXml = 'xml declaration stuff';
echo getThisXML($thisXML);
Or pass the variable by reference:
或者通过引用传递变量：
$thisXml = 'xml declaration stuff';
function getThisXML(&$thisXML){
...
return $thisXml;
}
getThisXML($thisXML);
echo $thisXml;
回答by Gumbo
回答by Jorge Niedbalski R.
You are trying to use a variable defined inside the function scope.
您正在尝试使用在函数作用域内定义的变量。
Use:
用：
$thisXML;
function do(){
global $thisXML;
$thisXML = "foobar";
}
print $thisXML;
回答by Facebook Staff are Complicit
Returning a variable doesn't mean that it affects that variable globally, it means the function call evaluates to that value where it's used.
返回一个变量并不意味着它会全局影响该变量，这意味着函数调用会在使用它的地方评估该值。
$my_var = 5;
function my_func() {
$my_var = 10;
return $my_var;
}
print my_func();
print "\n";
print $my_var;
This will print
这将打印
10
5
回答by Hamid Ghp
You can create function in php this way:
<?php
$name = array("ghp", "hamid", "amin", "Linux");
function find()
{
$find = 0;
if(in_array('hamid', $name))
{
$find = 1;
return $find;
}
else
{
return $find;
}
}
//###################
$answare = find();
echo $answare;
?>
