Html HTML如何使用javascript清除输入？
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HTML how to clear input using javascript?
提问by Lucas Ferraz
I have this INPUT, it will clear everytime we click inside of it.
我有这个输入，每次我们点击它时它都会清除。
The problem: I want to clear only if value = [email protected]
问题：我只想在 value = [email protected] 时清除
<script type="text/javascript">
function clearThis(target) {
target.value= "";
}
</script>
<input type="text" name="email" value="[email protected]" size="30" onfocus="clearThis(this)">
Can someone help me to do this? I don't know how to compare, I already tried but no success.
有人可以帮我做到这一点吗？我不知道如何比较，我已经尝试过但没有成功。
回答by David Scott
<script type="text/javascript">
function clearThis(target){
if(target.value=='[email protected]'){
target.value= "";}
}
</script>
Is this really what your looking for?
这真的是你要找的吗？
回答by SubLock69
You could use a placeholder because it does it for you, but for old browsers that don't support placeholder, try this:
您可以使用占位符，因为它适合您，但对于不支持占位符的旧浏览器，请尝试以下操作：
<script>
function clearThis(target) {
if (target.value == "[email protected]") {
target.value = "";
}
}
function replace(target) {
if (target.value == "" || target.value == null) {
target.value == "[email protected]";
}
}
</script>
<input type="text" name="email" value="[email protected]" size="x" onfocus="clearThis(this)" onblur="replace(this)" />
CODE EXPLAINED: When the text box has focus, clear the value. When text box is not focused AND when the box is blank, replace the value.
代码解释：当文本框获得焦点时，清除该值。当文本框未聚焦且框为空白时，替换值。
I hope that works, I have been having the same issue, but then I tried this and it worked for me.
我希望这有效，我一直有同样的问题，但后来我尝试了这个，它对我有用。
回答by Bugaloo
you can use attribute placeholder
你可以使用属性 placeholder
<input type="text" name="email" placeholder="[email protected]" size="30" />
or try this for older browsers
或者在旧浏览器上试试这个
<input type="text" name="email" value="[email protected]" size="30" onblur="if(this.value==''){this.value='[email protected]';}" onfocus="if(this.value=='[email protected]'){this.value='';}">
回答by Duck
You don't need to bother with that. Just write
你不需要为此烦恼。写就好了
<input type="text" name="email" placeholder="[email protected]" size="30">
replace the value with placeholder
用占位符替换值
回答by Sai Gopi N
instead of clearing the name text use placeholderattribute it is good practice
而不是清除名称文本使用占位符属性，这是一种很好的做法
<input type="text" placeholder="name" name="name">
回答by Juan Prendas
For me this is the best way:
对我来说，这是最好的方法：
<form id="myForm">
First name: <input type="text" name="fname"><br>
Last name: <input type="text" name="lname"><br><br>
<input type="button" onclick="myFunction()" value="Reset form">
</form>
<script>
function myFunction() {
document.getElementById("myForm").reset();
}
</script>
回答by Raitom
Try this :
尝试这个 ：
<script type="text/javascript">
function clearThis(target){
if(target.value == "[email protected]")
{
target.value= "";
}
}
</script>
回答by Adam
<script type="text/javascript">
function clearThis(target){
if (target.value === "[email protected]") {
target.value= "";
}
}
</script>
<input type="text" name="email" value="[email protected]" size="30" onfocus="clearThis(this)">
Try it out here: http://jsfiddle.net/2K3Vp/
在这里试试：http: //jsfiddle.net/2K3Vp/
