如何使用 ID 变量选择 jQuery 中的元素？

例如，下面选择 id = “2”的除法:

row = $("body").find("#2");

我该怎么做呢:

row_id = 5;
row = $("body").find(row_id);

上面的语法产生了一个错误。

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小开

I don't know much about jQuery, but try this:

row_id = "#5";
row = $("body").find(row_id);

Edit: Of course, if the variable is a number, you have to add "#" to the front:

row_id = 5
row = $("body").find("#"+row_id);

小开

You can do it like this:

row_id = 5;
row = $("body").find('#'+row_id);

小开

最佳答案

row = $("body").find('#' + row_id);

More importantly doing the additional body.find has no impact on performance. The proper way to do this is simply:

row = $('#' + row_id);

小开

There are two problems with your code

To find an element by ID you must prefix it with a "#"
You are attempting to pass a Number to the find function when a String is required (passing "#" + 5 would fix this as it would convert the 5 to a "5" first)

小开

The shortest way would be:

$("#" + row_id)

Limiting the search to the body doesn't have any benefit.

Also, you should consider renaming your ids to something more meaningful (and HTML compliant as per Paolo's answer), especially if you have another set of data that needs to be named as well.

小开

Doing $('body').find(); is not necessary when looking up by ID; there is no performance gain.

Please also note that having an ID that starts with a number is not valid HTML:

ID and NAME tokens must begin with a letter ([A-Za-z]) and may be followed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods (".").