每个人都会遇到语法错误。即使是经验丰富的程序员也会出现拼写错误。对于新人来说,这只是学习过程的一部分。然而,通常很容易解释如下错误消息:
PHP解析错误:语法错误,在index.php第20行中出现意外的“{”
意想不到的符号并不总是真正的罪魁祸首。但是行号给出了从哪里开始查找的大致概念。
总是查看代码上下文。语法错误通常隐藏在前面提到的或前面的代码行中。将您的代码与手册中的语法示例进行比较。
但并不是所有情况都是一样的。但是有一些通用的步骤可以解决语法错误。
本文总结了常见的陷阱:
Unexpected T_STRING
Unexpected T_VARIABLE Unexpected '$varname' (T_VARIABLE)
Unexpected T_CONSTANT_ENCAPSED_STRING Unexpected T_ENCAPSED_AND_WHITESPACE
Unexpected $end
Unexpected T_FUNCTION…
Unexpected {Unexpected }Unexpected (Unexpected )
Unexpected [Unexpected ]
Unexpected T_IF Unexpected T_FOREACH Unexpected T_FOR Unexpected T_WHILE Unexpected T_DO Unexpected T_PRINT Unexpected T_ECHO
Unexpected T_LNUMBER
Unexpected ?
Unexpected continue (T_CONTINUE)Unexpected continue (T_BREAK)Unexpected continue (T_RETURN)
Unexpected '='
Unexpected T_INLINE_HTML…
Unexpected T_PAAMAYIM_NEKUDOTAYIM…
Unexpected T_OBJECT_OPERATOR…
Unexpected T_DOUBLE_ARROW…
Unexpected T_SL…
Unexpected T_BOOLEAN_OR…
Unexpected T_BOOLEAN_AND…
Unexpected T_IS_EQUAL
Unexpected T_IS_GREATER_OR_EQUAL
Unexpected T_IS_IDENTICAL
Unexpected T_IS_NOT_EQUAL
Unexpected T_IS_NOT_IDENTICAL
Unexpected T_IS_SMALLER_OR_EQUAL
Unexpected <
Unexpected >
Unexpected T_NS_SEPARATOR…
Unexpected character in input: '\' (ASCII=92) state=1
Unexpected 'public' (T_PUBLIC) Unexpected 'private' (T_PRIVATE) Unexpected 'protected' (T_PROTECTED) Unexpected 'final' (T_FINAL)…
Unexpected T_STATIC…
Unexpected T_CLASS…
Unexpected 'use' (T_USE)
Unexpected T_DNUMBER
Unexpected , (comma)
Unpexected . (period)
Unexpected ; (semicolon)
Unexpected * (asterisk)
Unexpected : (colon)
Unexpected ':', expecting ',' or ')'
Unexpected & (call-time pass-by-reference)
Unexpected .
密切相关的参考文献:
这个错误在PHP中意味着什么?(运行时错误)
解析错误:语法错误,意外的T_XXX
解析错误:语法错误,意外的T_ENCAPSED_AND_WHITESPACE
解析错误:语法错误,意外的T_VARIABLE
这个符号在PHP中是什么意思?(语言标记)
这些“聪明”的引号对PHP毫无意义
And:
php.net上的PHP手册和它的各种语言标记
或者维基百科关于PHP的语法介绍。
最后是我们的php标签维基。
虽然Stack Overflow也欢迎新手程序员,但它主要针对的是专业编程问题。
回答每个人的编码错误和狭窄的拼写错误被认为是离题了。
因此,在发布语法修正请求之前,请花时间遵循基本步骤。
如果你仍然必须这样做,请展示你自己的解决方案,尝试修复,以及你对看起来或可能错误的思考过程。
如果您的浏览器显示错误消息,如“SyntaxError: illegal character”,那么它实际上不是php相关的,而是javascript语法错误。
供应商代码引起的语法错误:最后,考虑一下,如果语法错误不是由编辑代码库引起的,而是在外部供应商包安装或升级之后引起的,则可能是由于PHP版本不兼容造成的,因此请根据平台设置检查供应商的要求。
One more reason to occurrence of these errors is unexpected whitespace like similar characters with-in code, the code lines seems to be perfect, but they contains some specific characters which are similar to break line or whitespace or tab but they not get parsed by the parser.
I face this issue when I try to put some code from webpage to the code editor by simply copy paste, I saw this error with array definition. everything was looking right in array definition. I can't sort out right error, finally I define this array in single line, then error was gone. then again I try to make that definition multiple like but manually adding break(Enter) for each array element and saved the file this time no parsing error by editor and also no error while running it.
For Example I faced issue with this snippet which was on one blog, actually can't post those snippets ,cause stack overflow already knows the problem with code.
然后在解决它之后,我的工作片段是,它看起来类似于一个显示解析错误
语法错误,意外的“auth”(T_CONSTANT_ENCAPSED_STRING),期待']'
public $aliases = [
'csrf'=> \CodeIgniter\Filters\CSRF::class,
'toolbar'=> \CodeIgniter\Filters\DebugToolbar::class,
'honeypot'=> \CodeIgniter\Filters\Honeypot::class,
'auth' => \App\Filters\Auth::class,
];
意外的T_CONSTANT_ENCAPSED_STRING意外的t_encapsed_and_空白
T_CONSTANT_ENCAPSED_STRING和T_ENCAPSED_AND_WHITESPACE是指带引号的“字符串”字面量。
它们在不同的上下文中使用,但语法问题非常相似。t_encaged…警告出现在双引号的字符串上下文中,而T_CONSTANT…字符串经常在普通PHP表达式或语句中出错。
Incorrect variable interpolation
And it comes up most frequently for incorrect PHP variable interpolation:
⇓ ⇓
echo "Here comes a $wrong['array'] access";
Quoting arrays keys is a must in PHP context. But in double quoted strings (or HEREDOCs) this is a mistake. The parser complains about the contained single quoted 'string', because it usually expects a literal identifier / key there.
More precisely it's valid to use PHP2-style simple syntax within double quotes for array references:
echo "This is only $valid[here] ...";
Nested arrays or deeper object references however require the complex curly string expression syntax:
echo "Use {$array['as_usual']} with curly syntax.";
If unsure, this is commonly safer to use. It's often even considered more readable. And better IDEs actually use distinct syntax colorization for that.
Missing concatenation
If a string follows an expression, but lacks a concatenation or other operator, then you'll see PHP complain about the string literal:
⇓
print "Hello " . WORLD " !";
While it's obvious to you and me, PHP just can't guess that the string was meant to be appended there.
Confusing string quote enclosures
The same syntax error occurs when confounding string delimiters. A string started by a single ' or double " quote also ends with the same.
⇓
print "<a href="' . $link . '">click here</a>";
⌞⎽⎽⎽⎽⎽⎽⎽⎽⌟⌞⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⌟⌞⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⎽⌟
That example started with double quotes. But double quotes were also destined for the HTML attributes. The intended concatenation operator within however became interpreted as part of a second string in single quotes.
Tip: Set your editor/IDE to use slightly distinct colorization for single and double quoted strings. (It also helps with application logic to prefer e.g. double quoted strings for textual output, and single quoted strings only for constant-like values.)
This is a good example where you shouldn't break out of double quotes in the first place. Instead just use proper \" escapes for the HTML attributes´ quotes:
print "<a href=\"{$link}\">click here</a>";
While this can also lead to syntax confusion, all better IDEs/editors again help by colorizing the escaped quotes differently.
Missing opening quote
Equivalently are forgotten opening "/' quotes a recipe for parser errors:
⇓
make_url(login', 'open');
Here the ', ' would become a string literal after a bareword, when obviously login was meant to be a string parameter.
Array lists
If you miss a , comma in an array creation block, the parser will see two consecutive strings:
array( ⇓
"key" => "value"
"next" => "....",
);
Note that the last line may always contain an extra comma, but overlooking one in between is unforgivable. Which is hard to discover without syntax highlighting.
Function parameter lists
The same thing for function calls:
⇓
myfunc(123, "text", "and" "more")
Runaway strings
A common variation are quite simply forgotten string terminators:
⇓
mysql_evil("SELECT * FROM stuffs);
print "'ok'";
⇑
Here PHP complains about two string literals directly following each other. But the real cause is the unclosed previous string of course.
HEREDOC indentation
Prior PHP 7.3, the heredoc string end delimiter can't be prefixed with spaces:
print <<< HTML
<link..>
HTML;
⇑
Solution: upgrade PHP or find a better hoster.
另请参阅
PHP中关联数组的插值(双引号字符串)
语法错误,意外的T_CONSTANT_ENCAPSED_STRING
语法错误,PHP中意外的T_CONSTANT_ENCAPSED_STRING
SQL查询中出现意外的T_CONSTANT_ENCAPSED_STRING错误
意想不到的美元结束
当PHP谈到“意外的$end”时,这意味着您的代码在解析器期望更多代码时结束了。(如果从字面上理解,这个信息有点误导。它不是关于一个名为“$end”的变量,就像新来者有时认为的那样。它指的是“文件的结束”,EOF。)
原因:代码块/和函数或类声明的{和}不平衡。
它几乎总是缺少一个}花括号来关闭前面的代码块。它的意思是,解析器希望找到一个结束},但实际上到达了文件的末尾。
同样,使用适当的缩进来避免此类问题。
使用带有括号匹配的IDE,找出}错误的地方。
在大多数ide和文本编辑器中都有快捷键:
NetBeans, PhpStorm, Komodo: Ctrl[和Ctrl]
Eclipse, Aptana: CtrlShiftP
Atom, Sublime: Ctrlm - Zend Studio Ctrlm
Geany, notepad++: CtrlB - Joe: CtrlG - Emacs: C-M-n - Vim: %
大多数ide还突出显示匹配的大括号、方括号和圆括号。
这使得检查它们的相关性变得非常容易:
无端接的表达式
对于未结束的表达式或语句,也会出现意外的$end语法/解析器错误:
$var = func(1,
?>EOF
因此,首先查看脚本的末尾。拖尾;在任何PHP脚本中,最后一条语句通常是多余的。但你应该有一个。正是因为它缩小了这些语法问题的范围。特别是在您发现自己在脚本末尾添加了更多语句之后。
缩进的HEREDOC标记
另一种常见情况出现在HEREDOC或NOWDOC字符串中。如果前面有空格、制表符等,终止标记将被忽略:
print <<< END
Content...
Content....
END;
# ↑ terminator isn't exactly at the line start
因此,解析器假定HEREDOC字符串将一直持续到文件的末尾(因此是“意外的$end”)。几乎所有的ide和语法高亮编辑器都会明确显示或发出警告。
转义的引号
如果你在字符串中使用\,它有一个特殊的含义。这称为“转义字符”,通常告诉解析器按字面意思取下一个字符。
示例:echo 'Jim said \'Hello\ ";将打印Jim说'hello'
如果转义字符串的结束引号,结束引号将被字面上理解,而不是像预期的那样,即作为字符串的一部分而不是结束字符串的可打印引号。这通常会在打开下一个字符串后或脚本结束时显示为解析错误。
在Windows中指定路径时非常常见的错误:“C:\xampp\htdocs\”是错误的。你需要“C:\\xampp\\htdocs\\ \”。另外,PHP通常会转换unix风格的路径(例如。“C:/xampp/htdocs/”)到Windows的正确路径。
替代语法
在模板中使用语句/代码块的替代语法时,很少会看到这种语法错误。使用if:和else:和一个缺失的endif;为例。
参见:
PHP语法错误“意外$end”
解析错误:语法错误,在我的PHP代码文件意外结束
解析错误语法错误文件意外结束,使用PHP
PHP解析错误:语法错误,CodeIgniter视图中的文件意外结束
解析错误:语法错误,文件意外结束(注册脚本)
“解析错误:语法错误,意外$end”为我的uni注册分配
修复PHP错误:PHP错误#3:文件意外结束
意想不到的T_STRING
T_STRING有点用词不当。它不引用引用的“字符串”。这意味着遇到了原始标识符。这可以是空白的单词、剩余的CONSTANT或函数名、被遗忘的不带引号的字符串或任何纯文本。
Misquoted strings
This syntax error is most common for misquoted string values however. Any unescaped and stray " or ' quote will form an invalid expression:
⇓ ⇓
echo "<a href="http://example.com">click here</a>";
Syntax highlighting will make such mistakes super obvious. It's important to remember to use backslashes for escaping \" double quotes, or \' single quotes - depending on which was used as string enclosure.
For convenience you should prefer outer single quotes when outputting plain HTML with double quotes within.
Use double quoted strings if you want to interpolate variables, but then watch out for escaping literal " double quotes.
For lengthier output, prefer multiple echo/print lines instead of escaping in and out. Better yet consider a HEREDOC section.
Another example is using PHP entry inside HTML code generated with PHP:
$text = '<div>some text with <?php echo 'some php entry' ?></div>'
This happens if $text is large with many lines and developer does not see the whole PHP variable value and focus on the piece of code forgetting about its source. Example is here
See also What is the difference between single-quoted and double-quoted strings in PHP?.
Unclosed strings
If you miss a closing " then a syntax error typically materializes later. An unterminated string will often consume a bit of code until the next intended string value:
⇓
echo "Some text", $a_variable, "and some runaway string ;
success("finished");
⇯
It's not just literal T_STRINGs which the parser may protest then. Another frequent variation is an Unexpected '>' for unquoted literal HTML.
Non-programming string quotes
If you copy and paste code from a blog or website, you sometimes end up with invalid code. Typographic quotes aren't what PHP expects:
$text = ’Something something..’ + ”these ain't quotes”;
Typographic/smart quotes are Unicode symbols. PHP treats them as part of adjoining alphanumeric text. For example ”these is interpreted as a constant identifier. But any following text literal is then seen as a bareword/T_STRING by the parser.
The missing semicolon; again
If you have an unterminated expression in previous lines, then any following statement or language construct gets seen as raw identifier:
⇓
func1()
function2();
PHP just can't know if you meant to run two functions after another, or if you meant to multiply their results, add them, compare them, or only run one || or the other.
Short open tags and <?xml headers in PHP scripts
This is rather uncommon. But if short_open_tags are enabled, then you can't begin your PHP scripts with an XML declaration:
⇓
<?xml version="1.0"?>
PHP will see the <? and reclaim it for itself. It won't understand what the stray xml was meant for. It'll get interpreted as constant. But the version will be seen as another literal/constant. And since the parser can't make sense of two subsequent literals/values without an expression operator in between, that'll be a parser failure.
Invisible Unicode characters
A most hideous cause for syntax errors are Unicode symbols, such as the non-breaking space. PHP allows Unicode characters as identifier names. If you get a T_STRING parser complaint for wholly unsuspicious code like:
<?php
print 123;
You need to break out another text editor. Or an hexeditor even. What looks like plain spaces and newlines here, may contain invisible constants. Java-based IDEs are sometimes oblivious to an UTF-8 BOM mangled within, zero-width spaces, paragraph separators, etc. Try to reedit everything, remove whitespace and add normal spaces back in.
You can narrow it down with with adding redundant ; statement separators at each line start:
<?php
;print 123;
The extra ; semicolon here will convert the preceding invisible character into an undefined constant reference (expression as statement). Which in return makes PHP produce a helpful notice.
The `$` sign missing in front of variable names
Variables in PHP are represented by a dollar sign followed by the name of the variable.
The dollar sign ($) is a sigil that marks the identifier as a name of a variable. Without this sigil, the identifier could be a language keyword or a constant.
This is a common error when the PHP code was "translated" from code written in another language (C, Java, JavaScript, etc.). In such cases, a declaration of the variable type (when the original code was written in a language that uses typed variables) could also sneak out and produce this error.
Escaped Quotation marks
If you use \ in a string, it has a special meaning. This is called an "Escape Character" and normally tells the parser to take the next character literally.
Example: echo 'Jim said \'Hello\''; will print Jim said 'hello'
If you escape the closing quote of a string, the closing quote will be taken literally and not as intended, i.e. as a printable quote as part of the string and not close the string. This will show as a parse error commonly after you open the next string or at the end of the script.
Very common error when specifiying paths in Windows: "C:\xampp\htdocs\" is wrong. You need "C:\\xampp\\htdocs\\".
Typed properties
You need PHP ≥7.4 to use property typing such as:
public stdClass $obj;
意想不到的T_VARIABLE
一个“意外的T_VARIABLE”意味着有一个字面的$变量名,它不适合当前表达式/语句结构。
Missing semicolon
It most commonly indicates a missing semicolon in the previous line. Variable assignments following a statement are a good indicator where to look:
⇓
func1()
$var = 1 + 2; # parse error in line +2
String concatenation
A frequent mishap are string concatenations with forgotten . operator:
⇓
print "Here comes the value: " $value;
Btw, you should prefer string interpolation (basic variables in double quotes) whenever that helps readability. Which avoids these syntax issues.
String interpolation is a scripting language core feature. No shame in utilizing it. Ignore any micro-optimization advise about variable . concatenation being faster. It's not.
Missing expression operators
Of course the same issue can arise in other expressions, for instance arithmetic operations:
⇓
print 4 + 7 $var;
PHP can't guess here if the variable should have been added, subtracted or compared etc.
Lists
Same for syntax lists, like in array populations, where the parser also indicates an expected comma , for example:
⇓
$var = array("1" => $val, $val2, $val3 $val4);
Or functions parameter lists:
⇓
function myfunc($param1, $param2 $param3, $param4)
Equivalently do you see this with list or global statements, or when lacking a ; semicolon in a for loop.
Class declarations
This parser error also occurs in class declarations. You can only assign static constants, not expressions. Thus the parser complains about variables as assigned data:
class xyz { ⇓
var $value = $_GET["input"];
Unmatched } closing curly braces can in particular lead here. If a method is terminated too early (use proper indentation!), then a stray variable is commonly misplaced into the class declaration body.
Variables after identifiers
You can also never have a variable follow an identifier directly:
⇓
$this->myFunc$VAR();
Btw, this is a common example where the intention was to use variable variables perhaps. In this case a variable property lookup with $this->{"myFunc$VAR"}(); for example.
Take in mind that using variable variables should be the exception. Newcomers often try to use them too casually, even when arrays would be simpler and more appropriate.
Missing parentheses after language constructs
Hasty typing may lead to forgotten opening or closing parenthesis
for if and for and foreach statements:
⇓
foreach $array as $key) {
Solution: add the missing opening ( between statement and variable.
⇓
if ($var = pdo_query($sql) {
$result = …
The curly { brace does not open the code block, without closing the if expression with the ) closing parenthesis first.
Else does not expect conditions
⇓
else ($var >= 0)
Solution: Remove the conditions from else or use elseif.
Need brackets for closure
⇓
function() use $var {}
Solution: Add brackets around $var.
Invisible whitespace
As mentioned in the reference answer on "Invisible stray Unicode" (such as a non-breaking space), you might also see this error for unsuspecting code like:
<?php
⇐
$var = new PDO(...);
It's rather prevalent in the start of files and for copy-and-pasted code. Check with a hexeditor, if your code does not visually appear to contain a syntax issue.
另请参阅
搜索:意外T_VARIABLE