jQuery将所有类文本的总和作为数字

我希望在名为sent的类中将所有文本汇总为数字，但当我警告下面的代码时，它的输出为零：

var sum = 0;            
var thedate = $(".date:contains('15th February 2012')");

   $(thedate).each(function() {              
    var sents = $(this).next('.sent').text();

    var sentsnumb = parseFloat(sents);

        sum += Number($(sentsnumb));

});
    alert(sum);

这是我的html：

<tr>
   <td class="date">15th February 2012</td>
   <td class="sent"> 5</td>
</tr>
<tr>
   <td class="date">15th February 2012</td>
   <td class="sent"> 5</td>
</tr>
<tr>
   <td class="date">15th February 2012</td>
   <td class="sent"> 10</td>
</tr>
<tr>
   <td class="date">15th February 2012</td>
   <td class="sent"> 10</td>
</tr>

上面的期望输出是数字30。

请尝试以下方法：-

var sum = 0;            
var thedate = $(".date:contains('15th February 2012')");

   $(thedate).each(function() {              
    var sents = $(this).next('.sent').text();
    sum = sum + Number(sents);
});

alert(sum);​

实际问题是$sentsumb。应将其替换为Sentsumb

请尝试以下方法：-

var sum = 0;            
var thedate = $(".date:contains('15th February 2012')");

   $(thedate).each(function() {              
    var sents = $(this).next('.sent').text();
    sum = sum + Number(sents);
});

alert(sum);​

实际问题是$sentsumb。应将其替换为Sentsumb

尝试以下操作：

var sum = 0;             
var thedate = $(".date:contains('15th February 2012')"); 

$(thedate).each(function() {               
   var sents = $(this).next('.sent').text(); 
   var sentsnumb = parseFloat(sents); 
   sum += sentsnumb; 
}); 
alert(sum); 

试试这个：

var sum = 0;             
var thedate = $(".date:contains('15th February 2012')"); 

$(thedate).each(function() {               
   var sents = $(this).next('.sent').text(); 
   var sentsnumb = parseFloat(sents); 
   sum += sentsnumb; 
}); 
alert(sum); 

---

您不需要通过jQuery$函数传递所有信息

var sum = 0;
var thedate = $(".date:contains('15th February 2012')");

thedate.each(function() { // `thedate` is already a jQuery object, no need for `$()`
    var sents = $(this).next('.sent').text();

    var sentsnumb = parseInt(sents, 10); // use parseInt if your values don't have decimals

    sum += sentsnumb; // sentsnum is a float, do not use `$()` (or Number)
});

alert(sum);​

---

此外，您不能将标签放在外部，请确保您的HMTL有效。

您不需要通过jQuery$函数传递所有内容

var sum = 0;
var thedate = $(".date:contains('15th February 2012')");

thedate.each(function() { // `thedate` is already a jQuery object, no need for `$()`
    var sents = $(this).next('.sent').text();

    var sentsnumb = parseInt(sents, 10); // use parseInt if your values don't have decimals

    sum += sentsnumb; // sentsnum is a float, do not use `$()` (or Number)
});

alert(sum);​

此外，您不能在外部使用标记，请确保您的HMTL有效。

这一点有效：请参阅JSFIDLE：您需要使用Number函数的原因是。text返回一个文本字符串。Number将该文本转换回一个可以求和的数值。此操作有效：请参阅jsfiddle：需要使用Number函数的原因是。text返回一个文本字符串。数字将该文本转换回可以求和的数值。