<!DOCTYPE html><html><head> <title></title> <script type="text/javascript"> window.onload=function(){ var oIpt1=document.getElementById('ipt1'); var oBtn1=document.getElementById('btn1'); oBtn1.onclick=function(){ var oValue=oIpt1.oValue; if(oValue.length>10){ return false; }else{ return true; } } } </script></head><body><form> <input type="text" id="ipt1"> <button type="submit" id="btn1">提交</button></form></body></html>
1 回答
侃侃尔雅
TA贡献1801条经验 获得超16个赞
//你写的js是在页面加载的时候运行的。你想要实现的需要在页面加载完之后运行
好吧，放在onload里还是可以的
<!DOCTYPE html><html><head>
<title></title></head><body><form>
<input type="text" id="ipt1">
<button type="submit" id="btn1">提交</button></form>
<script type="text/javascript">
var oBtn1=document.getElementById('btn1');
oBtn1.onclick=function(e){ var oIpt1=document.getElementById('ipt1'); var oValue=oIpt1.value; //你写的是var oValue=oIpt1.oValue;
if(oValue.length>10){
e.preventDefault();
}else{ console.log(true);
}
} </script></body></html>添加回答
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