加载.js时出现TypeError

Question

我之前有代码，但控制台显示TypeError: $不是第一行的函数:(你能帮我讲道理吗?谢谢!

$('.day.event').parent().each(function (i, e) {
var element = $(e);
var prevElement=$(e).prev();
var hasPrevElement = true;
if(prevElement.size() === 0) {
var prevRow = element.parent().prev();
if(prevRow.size() === 0) {
hasPrevElement = false;
}
prevElement = prevRow.children().last();
}
var nextElement=$(e).next();
var hasNextElement = true;
if(nextElement.size() === 0) {
var nextRow = element.parent().next();
if(nextRow.size() === 0) {
hasNextElement = false;
}
nextElement = nextRow.children().first();
}
if(hasPrevElement && prevElement.children().first().attr("class").indexOf("event") === -1 || !hasPrevElement) {
element.addClass('first-day')
}
if(hasNextElement && nextElement.children().first().attr("class").indexOf("event") === -1) {
nextElement.addClass('after-event');
}

});

Answer 1

您应该像@Wendelin所说的那样在上述代码之前导入jQuery库，或者检查文件的路径