javascript 输入的jQuery keyup值
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jQuery keyup value of input
提问by Gabriel Uhlí?
i need to display value of <input>into the <span>and when label become empty, change value of span to "Video title". But always i type something into the <input>and then delete it, the <input>still have "" value so <span>display nothing. Thanks for help. (And sorry for my bad english)
我需要显示<input>into the 的值，<span>当标签变空时，将 span 的值更改为“视频标题”。但是我总是在里面输入一些东西<input>然后删除它，<input>仍然有“”值所以<span>什么都不显示。感谢帮助。（对不起，我的英语不好）
Here is my code:
这是我的代码：
$("#newVideoName").keyup(function(){
var newVideoName = $("#newVideoName").val();
if(newVideoName == ""){
$("#newVideoNameLabel").html("Video title");
}
});
<input type="text" id="newVideoName">
<span id="newVideoNameLabel"></span>
采纳答案by undefined
$("#newVideoName").keyup(function() {
$("#newVideoNameLabel").text(this.value ? this.value : "Video title");
});
