无法修复语法错误：意外的令牌'＆lt;'

Question

我一直试图修复一段javascript代码，但没有运气。语法看起来正确，但我一直得到一个意外的令牌'＆lt;'语法错误。

请不要将此问题标记为重复，因为我在此网站上找不到问题的答案。

使用Javascript：

// Function to get elements by class name for DOM fragment and tag name
 function getElementsByClassName(objElement, strTagName, strClassName)
{
var objCollection = objElement.getElementsByTagName(strTagName);
var arReturn = [];
var strClass, arClass, iClass, iCounter;

for(iCounter=0; iCounter<objCollection.length; iCounter++)
{
    strClass = objCollection[iCounter].className;
    if (strClass)
    {
        arClass = strClass.split(' ');
        for (iClass=0; iClass<arClass.length; iClass++)
        {
            if (arClass[iClass] == strClassName)
            {
                arReturn.push(objCollection[iCounter]);
                break;
            }
        }
    }
}

objCollection = null;
return (arReturn);
}

var drag = {
objCurrent : null,

arTargets : ['Fav', 'Tol', 'Rej'],

initialise : function(objNode)
{
    // Add event handlers
    objNode.onmousedown = drag.start;
    objNode.onclick = function() {this.focus();};
    objNode.onkeydown = drag.keyboardDragDrop;
    document.body.onclick = drag.removePopup;
},

keyboardDragDrop : function(objEvent)
{
    objEvent = objEvent || window.event;
    drag.objCurrent = this;
    var arChoices = ['Favourite artists', 'Tolerable artists', 'Rejected artists'];
    var iKey = objEvent.keyCode;
    var objItem = drag.objCurrent;

        var strExisting = objItem.parentNode.getAttribute('id');
        var objMenu, objChoice, iCounter;

        if (iKey == 32)
        {
            document.onkeydown = function(){return objEvent.keyCode==38 || objEvent.keyCode==40 ? false : true;};
            // Set ARIA properties
            drag.objCurrent.setAttribute('aria-grabbed', 'true');
            drag.objCurrent.setAttribute('aria-owns', 'popup');
            // Build context menu
            objMenu = document.createElement('ul');
            objMenu.setAttribute('id', 'popup');
            objMenu.setAttribute('role', 'menu');
            for (iCounter=0; iCounter<arChoices.length; iCounter++)
            {
                if (drag.arTargets[iCounter] != strExisting)
                {
                    objChoice = document.createElement('li');
                    objChoice.appendChild(document.createTextNode(arChoices[iCounter]));
                    objChoice.tabIndex = -1;
                    objChoice.setAttribute('role', 'menuitem');
                    objChoice.onmousedown = function() {drag.dropObject(this.firstChild.data.substr(0, 3));};
                    objChoice.onkeydown = drag.handleContext;
                    objChoice.onmouseover = function() {if (this.className.indexOf('hover') < 0) {this.className += ' hover';} };
                    objChoice.onmouseout = function() {this.className = this.className.replace(/\s*hover/, ''); };
                    objMenu.appendChild(objChoice);
                }
            }
            objItem.appendChild(objMenu);
            objMenu.firstChild.focus();
            objMenu.firstChild.className = 'focus';
            drag.identifyTargets(true);
        }
},

removePopup : function()
{
    document.onkeydown = null;

    var objContext = document.getElementById('popup');

    if (objContext)
    {
        objContext.parentNode.removeChild(objContext);
    }
},

handleContext : function(objEvent)
{
    objEvent = objEvent || window.event;
    var objItem = objEvent.target || objEvent.srcElement;
    var iKey = objEvent.keyCode;
    var objFocus, objList, strTarget, iCounter;

    // Cancel default behaviour
    if (objEvent.stopPropagation)
    {
        objEvent.stopPropagation();
    }
    else if (objEvent.cancelBubble)
    {
        objEvent.cancelBubble = true;
    }
    if (objEvent.preventDefault)
    {
        objEvent.preventDefault();
    }
    else if (objEvent.returnValue)
    {
        objEvent.returnValue = false;
    }

    switch (iKey)
    {
        case 38 : // Down arrow
            objFocus = objItem.nextSibling;
            if (!objFocus)
            {
                objFocus = objItem.previousSibling;
            }
            objItem.className = '';
            objFocus.focus();
            objFocus.className = 'focus';
            break;
        case 40 : // Up arrow
            objFocus = objItem.previousSibling;
            if (!objFocus)
            {
                objFocus = objItem.nextSibling;
            }
            objItem.className = '';
            objFocus.focus();
            objFocus.className = 'focus';
            break;
        case 13 : // Enter
            strTarget = objItem.firstChild.data.substr(0, 3);
            drag.dropObject(strTarget);
            break;
        case 27 : // Escape
        case 9  : // Tab
            drag.objCurrent.removeAttribute('aria-owns');
            drag.objCurrent.removeChild(objItem.parentNode);
            drag.objCurrent.focus();
            for (iCounter=0; iCounter<drag.arTargets.length; iCounter++)
            {
                objList = document.getElementById(drag.arTargets[iCounter]);
                drag.objCurrent.setAttribute('aria-grabbed', 'false');
                objList.removeAttribute('aria-dropeffect');
                objList.className = '';
            }
            break;
    }
},

start : function(objEvent)
{
    objEvent = objEvent || window.event;
    drag.removePopup();
    // Initialise properties
    drag.objCurrent = this;

    drag.objCurrent.lastX = objEvent.clientX;
    drag.objCurrent.lastY = objEvent.clientY;
    drag.objCurrent.style.zIndex = '2';
    drag.objCurrent.setAttribute('aria-grabbed', 'true');

    document.onmousemove = drag.drag;
    document.onmouseup = drag.end;
    drag.identifyTargets(true);

    return false;
},

drag : function(objEvent)
{
    objEvent = objEvent || window.event;

    // Calculate new position
    var iCurrentY = objEvent.clientY;
    var iCurrentX = objEvent.clientX;
    var iYPos = parseInt(drag.objCurrent.style.top, 10);
    var iXPos = parseInt(drag.objCurrent.style.left, 10);
    var iNewX, iNewY;

    iNewX = iXPos + iCurrentX - drag.objCurrent.lastX;
    iNewY = iYPos + iCurrentY - drag.objCurrent.lastY;

    drag.objCurrent.style.left = iNewX + 'px';
    drag.objCurrent.style.top = iNewY + 'px';
    drag.objCurrent.lastX = iCurrentX;
    drag.objCurrent.lastY = iCurrentY;

    return false;
},

calculatePosition : function (objElement, strOffset)
{
    var iOffset = 0;

    // Get offset position in relation to parent nodes
    if (objElement.offsetParent)
    {
        do 
        {
            iOffset += objElement[strOffset];
            objElement = objElement.offsetParent;
        } while (objElement);
    }

    return iOffset;
},

identifyTargets : function (bHighlight)
{
    var strExisting = drag.objCurrent.parentNode.getAttribute('id');
    var objList, iCounter;

    // Highlight the targets for the current drag item
    for (iCounter=0; iCounter<drag.arTargets.length; iCounter++)
    {
        objList = document.getElementById(drag.arTargets[iCounter]);
        if (bHighlight && drag.arTargets[iCounter] != strExisting)
        {
            objList.className = 'highlight';
            objList.setAttribute('aria-dropeffect', 'move');
        }
        else
        {
            objList.className = '';
            objList.removeAttribute('aria-dropeffect');
        }
    }
},

getTarget : function()
{
    var strExisting = drag.objCurrent.parentNode.getAttribute('id');
    var iCurrentLeft = drag.calculatePosition(drag.objCurrent, 'offsetLeft');
    var iCurrentTop = drag.calculatePosition(drag.objCurrent, 'offsetTop');
    var iTolerance = 40;
    var objList, iLeft, iRight, iTop, iBottom, iCounter;

    for (iCounter=0; iCounter<drag.arTargets.length; iCounter++)
    {
        if (drag.arTargets[iCounter] != strExisting)
        {
            // Get position of the list
            objList = document.getElementById(drag.arTargets[iCounter]);
            iLeft = drag.calculatePosition(objList, 'offsetLeft') - iTolerance;
            iRight = iLeft + objList.offsetWidth + iTolerance;
            iTop = drag.calculatePosition(objList, 'offsetTop') - iTolerance;
            iBottom = iTop + objList.offsetHeight + iTolerance;

            // Determine if current object is over the target
            if (iCurrentLeft > iLeft && iCurrentLeft < iRight && iCurrentTop > iTop && iCurrentTop < iBottom)
            {
                return drag.arTargets[iCounter];
            }
        }
    }

    // Current object is not over a target
    return '';
},

dropObject : function(strTarget)
{
    var objClone, objOriginal, objTarget, objEmpty, objBands, objItem;

    drag.removePopup();

    if (strTarget.length > 0)
    {
        // Copy node to new target
        objOriginal = drag.objCurrent.parentNode;
        objClone = drag.objCurrent.cloneNode(true);

        // Remove previous attributes
        objClone.removeAttribute('style');
        objClone.className = objClone.className.replace(/\s*focused/, '');
        objClone.className = objClone.className.replace(/\s*hover/, '');

        // Add focus indicators
        objClone.onfocus = function() {this.className += ' focused'; };
        objClone.onblur = function() {this.className = this.className.replace(/\s*focused/, '');};
        objClone.onmouseover = function() {if (this.className.indexOf('hover') < 0) {this.className += ' hover';} };
        objClone.onmouseout = function() {this.className = this.className.replace(/\s*hover/, ''); };

        objTarget = document.getElementById(strTarget);
        objOriginal.removeChild(drag.objCurrent);
        objTarget.appendChild(objClone);
        drag.objCurrent = objClone;
        drag.initialise(objClone);

        // Remove empty node if there are artists in list
        objEmpty = getElementsByClassName(objTarget, 'li', 'empty');
        if (objEmpty[0])
        {
            objTarget.removeChild(objEmpty[0]);
        }

        // Add an empty node if there are no artists in list
        objBands = objOriginal.getElementsByTagName('li');
        if (objBands.length === 0)
        {
            objItem = document.createElement('li');
            objItem.appendChild(document.createTextNode('None'));
            objItem.className = 'empty';
            objOriginal.appendChild(objItem);
        }
    }
            // Reset properties
    drag.objCurrent.style.left = '0px';
    drag.objCurrent.style.top = '0px';

    drag.objCurrent.style.zIndex = 'auto';
    drag.objCurrent.setAttribute('aria-grabbed', 'false');
    drag.objCurrent.removeAttribute('aria-owns');

    drag.identifyTargets(false);
},

end : function()
{
    var strTarget = drag.getTarget();

    drag.dropObject(strTarget);

    document.onmousemove = null;
    document.onmouseup   = null;
    drag.objCurrent = null;
}
};

function init ()
{
var objItems = getElementsByClassName(document, 'li', 'draggable');
var objItem, iCounter;

for (iCounter=0; iCounter<objItems.length; iCounter++)
{
    // Set initial values so can be moved
    objItems[iCounter].style.top = '0px';
    objItems[iCounter].style.left = '0px';

    // Put the list items into the keyboard tab order
    objItems[iCounter].tabIndex = 0;

    // Set ARIA attributes for artists
    objItems[iCounter].setAttribute('aria-grabbed', 'false');
    objItems[iCounter].setAttribute('aria-haspopup', 'true');
    objItems[iCounter].setAttribute('role', 'listitem');

    // Provide a focus indicator
    objItems[iCounter].onfocus = function() {this.className += ' focused'; };
    objItems[iCounter].onblur = function() {this.className = this.className.replace(/\s*focused/, '');};
    objItems[iCounter].onmouseover = function() {if (this.className.indexOf('hover') < 0) {this.className += ' hover';} };
    objItems[iCounter].onmouseout = function() {this.className = this.className.replace(/\s*hover/, ''); };

    drag.initialise(objItems[iCounter]);
}

// Set ARIA properties on the drag and drop list, and set role of this region to application
for (iCounter=0; iCounter<drag.arTargets.length; iCounter++)
{
    objItem = document.getElementById(drag.arTargets[iCounter]);
    objItem.setAttribute('aria-labelledby', drag.arTargets[iCounter] + 'h');
    objItem.setAttribute('role', 'list');
}

objItem = document.getElementById('dragdrop');
objItem.setAttribute('role', 'application');


objItems = null;
}

window.onload = init;

Answer 1

这种类型的问题通常在发出一个AJAX请求时发生，该请求期望JSON或JavaScript作为响应，但它会接收HTML。

当期望JSON或JavaScript时，响应的文本必须由JavaScript解析器“eval”。如果接收并评估HTML代码为JSON或JavaScript，则低于<或大于>符号的存在将导致错误。