javascript 无法读取未定义的属性“元素” - 在 JS 控制台中
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StackOverFlow
Cannot Read Property 'Elements' of Undefined - in JS Console
提问by TheLettuceMaster
HTML form (outputed thru PHP)
HTML 表单（通过 PHP 输出）
$retVal .= "<form id= 'importSampleDataForm' name = 'importSampleDataForm' onsubmit = \"return false\" >\n";
// Form content edited out; it contains several dozen checkboxes
$retVal .= sprintf("<input type='button' class='wn_button' onclick='SaveMotorSkills();' value='Import Selected'>\n");
$retVal .= "</form>\n";
JavaScript / Ajax
JavaScript/Ajax
function SaveMotorSkills() // {{{
{
// {{{ Ajax Header
var httpRequest = CreateHttpRequest();
if (!httpRequest) {
DialogFail('AJAX initialization error. ', 1 );
return false;
} // }}}
var params = '_SaveMotorSkills=1';
for(i=0; i<document.importSampleDataForm.elements.length; i++) // line with error
{
params += "&" + document.importSampleDataForm.elements[i].name +
"=" + document.importSampleDataForm.elements[i].value ;
}
// edit out AJAX setup
httpRequest.send(params);
DialogSave("Saving...");
} // }}}
See "Line With Error Above" in forloop. JS Console says
请参阅for循环中的“上面有错误的行” 。JS 控制台说
Uncaught TypeError: Cannot read property 'elements' of undefined
Uncaught TypeError: Cannot read property 'elements' of undefined
I have looked at this code so much my eyes can't take it anymore. Does anyone else see anything I don't? I can add more code if needed.
我已经看了这么多代码，我的眼睛再也受不了了。有没有其他人看到我没有看到的东西？如果需要，我可以添加更多代码。
回答by Patrick
Try
尝试
document.getElementById('importSampleDataForm').elements.length
Also, nested forms are not allowed, so that also needs to be resolved.
此外，不允许嵌套表单，因此也需要解决。
