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Plugins/Validation/Methods/required

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[edit]

required( )

Makes the element always required.
Return false if the element is empty (text input) or unchecked (radio/checkbxo) or nothing selected (select).

Works with text inputs, selects, checkboxes and radio buttons.

To force a user to select an option from a select box, provide an empty options like <option value="">Choose...</option>


Examples:

Makes "field" always required. Nothing and blanks are invalid.

$("#myform").validate({
  rules: {
    field: "required"
  }
});


<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
                    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
  <script src="http://code.jquery.com/jquery-latest.js"></script>
  <script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/lib/jquery.delegate.js"></script>
<script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/jquery.validate.js"></script>
<script type="text/javascript">
jQuery.validator.setDefaults({
	debug: true,
	success: "valid"
});;
</script>

  <script>
  $(document).ready(function(){
    $("#myform").validate({
  rules: {
    field: "required"
  }
});
  });
  </script>
  <style>#field { margin-left: .5em; float: left; }
  	#field, label { float: left; font-family: Arial, Helvetica, sans-serif; font-size: small; }
	br { clear: both; }
	input { border: 1px solid black; margin-bottom: .5em;  }
	input.error { border: 1px solid red; }
	label.error {
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/unchecked.gif') no-repeat;
		padding-left: 16px;
		margin-left: .3em;
	}
	label.valid {
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/checked.gif') no-repeat;
		display: block;
		width: 16px;
		height: 16px;
	}
</style>
</head>
<body>
  
<form id="myform">
  <label for="field">Required: </label>
  <input class="left" id="field" name="field" />
  <br/>
  <input type="submit" value="Validate!" />
</form>

</body>
</html>

Makes the fruit select required.

$("#myform").validate({
  rules: {
    fruit: "required"
  }
});


<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
                    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
  <script src="http://code.jquery.com/jquery-latest.js"></script>
  <script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/lib/jquery.delegate.js"></script>
<script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/jquery.validate.js"></script>
<script type="text/javascript">
jQuery.validator.setDefaults({
	debug: true,
	success: "valid"
});;
</script>

  <script>
  $(document).ready(function(){
    $("#myform").validate({
  rules: {
    fruit: "required"
  }
});
  });
  </script>
  <style>#fruit { margin-left: .5em; float: left; }
  	#fruit, label { float: left; font-family: Arial, Helvetica, sans-serif; font-size: small; }
	br { clear: both; }
	input, select { border: 1px solid black; margin-bottom: .5em;  }
	select.error { border: 1px solid red; }
	label.error {
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/unchecked.gif') no-repeat;
		padding-left: 16px;
		margin-left: .3em;
	}
	label.valid {
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/checked.gif') no-repeat;
		display: block;
		width: 16px;
		height: 16px;
	}
</style>
</head>
<body>
  
<form id="myform">
  <label for="fruit">Please select a fruit</label>
  <select id="fruit" name="fruit" title="Please select something!"
    <option value=""></option>
    <option value="1">Banana</option>
    <option value="2">Apple</option>
    <option value="3">Peach</option>
  </select>
  <br/>
  <input type="submit" value="Validate!" />
</form>

</body>
</html>

Makes the gender radio buttons required.

$("#myform").validate({
  rules: {
    gender: "required"
  }
});


<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
                    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
  <script src="http://code.jquery.com/jquery-latest.js"></script>
  <script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/lib/jquery.delegate.js"></script>
<script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/jquery.validate.js"></script>
<script type="text/javascript">
jQuery.validator.setDefaults({
	debug: true,
	success: "valid"
});;
</script>

  <script>
  $(document).ready(function(){
    $("#myform").validate({
  rules: {
    gender: "required"
  }
});
  });
  </script>
  <style>label { float: left; font-family: Arial, Helvetica, sans-serif; font-size: small; }
	br { clear: both; }
	input { border: 1px solid black; margin-bottom: .5em;  }
	label.error {
		display:none;
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/unchecked.gif') no-repeat;
		padding-left: 16px;
		margin-left: .3em;
	}
	label.valid {
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/checked.gif') no-repeat;
		display: block;
		width: 16px;
		height: 16px;
	}
</style>
</head>
<body>
  
<form id="myform">
    <label for="gender_male">
      <input  type="radio" id="gender_male" value="m" name="gender" />
      Male
    </label>
    <label for="gender_female">
      <input  type="radio" id="gender_female" value="f" name="gender"/>
      Female
    </label>
    <label for="gender" class="error">Please select your gender</label>
  <br/>
  <input type="submit" value="Validate!" />
</form>

</body>
</html>

Makes the agree checkbox required.

$("#myform").validate({
  rules: {
    agree: "required"
  }
});


<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
                    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
  <script src="http://code.jquery.com/jquery-latest.js"></script>
  <script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/lib/jquery.delegate.js"></script>
<script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/jquery.validate.js"></script>
<script type="text/javascript">
jQuery.validator.setDefaults({
	debug: true,
	success: "valid"
});;
</script>

  <script>
  $(document).ready(function(){
    $("#myform").validate({
  rules: {
    agree: "required"
  }
});
  });
  </script>
  <style>#agree { margin-left: .5em; float: left; }
  	#agree, label { float: left; font-family: Arial, Helvetica, sans-serif; font-size: small; }
	br { clear: both; }
	input { border: 1px solid black; margin-bottom: .5em;  }
	input.error { border: 1px solid red; }
	label.error {
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/unchecked.gif') no-repeat;
		padding-left: 16px;
		margin-left: .3em;
	}
	label.valid {
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/checked.gif') no-repeat;
		display: block;
		width: 16px;
		height: 16px;
	}
</style>
</head>
<body>
  
<form id="myform">
  <label for="agree">Please agree to our policy</label>
  <input type="checkbox" id="agree" title="Please agree to our policy!" name="agree" />
  <br/>
  <input type="submit" value="Validate!" />
</form>

</body>
</html>

NameType


[edit]

required( dependency-expression )

Makes the element required, depending on the result of the given expression.
Return false if the element is empty (text input) or unchecked (radio/checkbxo) or nothing selected (select).

Works with all kind of text inputs, selects, checkboxes and radio buttons.

To force a user to select an option from a select box, provide an empty options like <option value="">Choose...</option>
Arguments:
dependency-expressionString
An expression (String) is evaluated in the context of the element's form, making the field required only if the expression returns more then one element.


Examples:

Makes details required only if #other is checked.

$("#myform").validate({
  rules: {
    details: {
      required: "#other:checked"
    }
  }, debug:true
});
$("#other").click(function() {
  $("#details").valid();
});



<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
                    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
  <script src="http://code.jquery.com/jquery-latest.js"></script>
  <script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/lib/jquery.delegate.js"></script>
<script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/jquery.validate.js"></script>
<script type="text/javascript">
jQuery.validator.setDefaults({
	debug: true,
	success: "valid"
});;
</script>

  <script>
  $(document).ready(function(){
    $("#myform").validate({
  rules: {
    details: {
      required: "#other:checked"
    }
  }, debug:true
});
$("#other").click(function() {
  $("#details").valid();
});

  });
  </script>
  <style>label { float: left; font-family: Arial, Helvetica, sans-serif; font-size: small; }
	br { clear: both; }
	input { border: 1px solid black; margin-bottom: .5em;  }
	label.error {
		display:none;
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/unchecked.gif') no-repeat;
		padding-left: 16px;
		margin-left: .3em;
	}
	label.valid {
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/checked.gif') no-repeat;
		display: block;
		width: 16px;
		height: 16px;
	}
</style>
</head>
<body>
  <form id="myform">
  <label for="other"><input id="other" type="checkbox" />Check to make next field required</label>
  <br/>
  <input id="details" name="details" />
  <br/>
  <input type="submit" value="Validate!" />
</form>
</body>
</html>

NameType


[edit]

required( dependency-callback )

Makes the element required, depending on the result of the given callback.
Return false if the element is empty (text input) or unchecked (radio/checkbxo) or nothing selected (select).

Works with all kind of text inputs, selects, checkboxes and radio buttons.

To force a user to select an option from a select box, provide an empty options like <option value="">Choose...</option>
Arguments:
dependency-callbackCallback
The function is executed with the element as it's only argument: If it returns true, the element is required.


Examples:

Makes details required only if #other is checked.

$("#myform").validate({
  rules: {
    age: {
      required: true,
      min: 3
    },
    parent: {
      required: function(element) {
        return $("#age").val() < 13;
      }
    }
  }
});
$("#age").blur(function() {
  $("#parent").valid();
});




<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" 
                    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
  <script src="http://code.jquery.com/jquery-latest.js"></script>
  <script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/lib/jquery.delegate.js"></script>
<script type="text/javascript" src="http://dev.jquery.com/view/trunk/plugins/validate/jquery.validate.js"></script>
<script type="text/javascript">
jQuery.validator.setDefaults({
	debug: true,
	success: "valid"
});;
</script>

  <script>
  $(document).ready(function(){
    $("#myform").validate({
  rules: {
    age: {
      required: true,
      min: 3
    },
    parent: {
      required: function(element) {
        return $("#age").val() < 13;
      }
    }
  }
});
$("#age").blur(function() {
  $("#parent").valid();
});


  });
  </script>
  <style>label { float: left; font-family: Arial, Helvetica, sans-serif; font-size: small; }
	br { clear: both; }
	input { border: 1px solid black; margin-bottom: .5em;  }
	label.error {
		display:none;
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/unchecked.gif') no-repeat;
		padding-left: 16px;
		margin-left: .3em;
	}
	label.valid {
		background: url('http://dev.jquery.com/view/trunk/plugins/validate/demo/images/checked.gif') no-repeat;
		display: block;
		width: 16px;
		height: 16px;
	}
</style>
</head>
<body>
  <form id="myform">
  <label>Age </label><input id="age" name="age" />
  <br/>
  <label>Parent </label><input id="parent" name="parent" />
  <br/>
  <input type="submit" value="Validate!" />
</form>
</body>
</html>

NameType


Retrieved from "http://docs.jquery.com/Plugins/Validation/Methods/required"