Why can't I display alert if text box has a value?
Question
I'm trying to get a function to run an if statement only if something has no value.
<script src="https://jqueryvalidation.org/files/lib/jquery-1.11.1.js"></script>
<script type="text/javascript">
function checkNSC() {
var confirmNSC = $("#SelectNsc");
if (confirmNSC.length == 0) {
alert("Please ensure all required fields are filled out")
}
else {
alert("NSC has value")
}
}
</script>
HTML:
<input type="text" id="SelectNsc" />
<button onclick="checkNSC();" id="myButton">My Button</button>
</div>
I'm trying to say if the value is 0 then to display an alert saying (Please ensure all fields are filled out". Otherwise say "NSC has a value"
Thanks,
3 answers
solution1
5 ACCPTED 2016-05-30 11:31:36
Should be,
var confirmNSC = $("#SelectNsc").val();
Because $("#SelectNsc") return a jquery object, so that $("#SelectNsc").length will always return a value greater than 0.
<script src = "https://jqueryvalidation.org/files/lib/jquery-1.11.1.js" > < /script>
<script type = "text/javascript" >
$(document).ready(function() {
$("#myButton").click(function() {
var confirmNSC = $("#SelectNsc").val().trim();
if (confirmNSC.length == 0) {
alert("Please ensure all required fields are filled out")
} else {
alert("NSC has value")
}
});
})
</script>
solution2
2 2016-05-30 11:35:28
Try this, It's working fine
<script src="https://jqueryvalidation.org/files/lib/jquery-1.11.1.js"></script> <script type="text/javascript"> function checkNSC() { var confirmNSC = $("#SelectNsc"); if (confirmNSC.val() =='') { alert("Please ensure all required fields are filled out") } else { alert("NSC has value") } } </script> <input type="text" id="SelectNsc" /> <button onclick="checkNSC();" id="myButton">My Button</button> </div>
solution3
1 2016-05-30 11:40:23
use this code :
<body>
<script src="https://jqueryvalidation.org/files/lib/jquery-1.11.1.js"></script>
<script type="text/javascript">
function checkNSC() {
var confirmNSC = document.getElementById("SelectNsc").value;
if (confirmNSC.length == 0) {
alert("Please ensure all required fields are filled out")
}
else {
alert("NSC has value")
}
}
</script>
<input type="text" id="SelectNsc" />
<button onclick="checkNSC();" id="myButton">My Button</button>
</body>
OR , use this code :
<body>
<script src="https://jqueryvalidation.org/files/lib/jquery-1.11.1.js"></script>
<script type="text/javascript">
function checkNSC() {
var confirmNSC = $("#SelectNsc").val();
if (confirmNSC.length == 0) {
alert("Please ensure all required fields are filled out")
}
else {
alert("NSC has value")
}
}
</script>
<input type="text" id="SelectNsc" />
<button onclick="checkNSC();" id="myButton">My Button</button>
</body>
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