get checked radio button value jquery by name with code examples

jQuery is a popular JavaScript library that provides many useful methods for manipulating HTML elements. One of the most common tasks in web development is getting the value of a selected radio button. In this article, we will explore different ways of getting the checked radio button value by name in jQuery.

Before we start, let's consider a simple HTML code for a group of radio buttons:

<form>
  <input type="radio" name="color" value="red">Red
  <input type="radio" name="color" value="blue">Blue
  <input type="radio" name="color" value="green">Green
</form>

The above code represents a form with three radio buttons, each with the same name "color". The name attribute is used to group radio buttons together so that only one radio button can be selected at a time.

Now, let's see how to get the value of the selected radio button by name.

Method 1: Using jQuery's val() Method

The simplest way to get the value of the selected radio button is by using the val() method. This method returns the value of the first element in the set of matched elements. In our case, the first matched element will be the selected radio button.

Here is the code for this method:

$(document).ready(function() {
  $("input[name='color']:checked").val();
});

In this code, the $(document).ready() function is used to ensure that the code runs after the page has finished loading. Then, the $("input[name='color']:checked") selector is used to select the checked radio button with the name "color". Finally, the val() method is used to get the value of the selected radio button.

Method 2: Using jQuery's :radio Selector

Another way to get the value of the selected radio button is by using the :radio selector. The :radio selector is used to select all radio buttons in a group.

Here is the code for this method:

$(document).ready(function() {
  var radioValue = $("input[name='color']:radio").filter(":checked").val();
});

In this code, the $("input[name='color']:radio") selector is used to select all radio buttons with the name "color". The filter(":checked") method is then used to filter out only the checked radio button. Finally, the val() method is used to get the value of the selected radio button.

Method 3: Using jQuery's each() Method

The each() method is used to loop through each element in a set of matched elements. This method can be used to loop through all radio buttons in a group and get the value of the selected radio button.

Here is the code for this method:

$(document).ready(function() {
  var radioValue;
  $("input[name='color']:radio").each(function() {
    if ($(this).is(":checked")) {
      radioValue = $(this).val();
    }
  });
});

In this code, the $("input[name='color']:radio") selector is used to select all radio buttons with the name "color". Then, the `each()

Radio Button Groups

It is important to note that radio buttons should always be grouped together using the same name attribute. This ensures that only one radio button in the group can be selected at a time.

Checked Property

The checked property is used to determine if a radio button is selected or not. If a radio button is selected, the checked property will be set to true.

$(document).ready(function() {
  var isChecked = $("input[name='color']:checked").prop("checked");
});

In this code, the prop() method is used to get the checked property of the selected radio button.

Setting the Value of a Radio Button

In addition to getting the value of a selected radio button, you can also set the value of a radio button programmatically. This is useful when you need to pre-select a radio button based on user data or some other condition.

$(document).ready(function() {
  $("input[name='color'][value='blue']").prop("checked", true);
});

In this code, the $("input[name='color'][value='blue']") selector is used to select the radio button with the name "color" and value "blue". Then, the prop("checked", true) method is used to set the checked property to true, effectively selecting the radio button.

Conclusion

In this article, we have explored different methods of getting the value of a selected radio button by name in jQuery. We have also discussed the importance of radio button groups and the checked property. Additionally, we have seen how to set the value of a radio button programmatically. With this knowledge, you should be able to easily manipulate radio buttons in your web projects.

Popular questions

1. How do you get the value of a selected radio button in jQuery?
   Answer: You can get the value of a selected radio button in jQuery by using the val() method on the selected radio button. For example, the following code would get the value of the selected radio button with the name "color":

$(document).ready(function() {
  var radioValue = $("input[name='color']:checked").val();
});

2. How do you group radio buttons together in HTML?
   Answer: Radio buttons should always be grouped together using the same name attribute in HTML. This ensures that only one radio button in the group can be selected at a time.

3. What is the checked property in radio buttons?
   Answer: The checked property is used to determine if a radio button is selected or not. If a radio button is selected, the checked property will be set to true.

4. How do you set the value of a radio button in jQuery?
   Answer: You can set the value of a radio button programmatically in jQuery by using the prop() method and setting the checked property to true. For example, the following code would set the radio button with the name "color" and value "blue" as selected:

$(document).ready(function() {
  $("input[name='color'][value='blue']").prop("checked", true);
});

5. What is the importance of radio button groups?
   Answer: The importance of radio button groups lies in the fact that only one radio button in a group can be selected at a time. Radio buttons should always be grouped together using the same name attribute to ensure that multiple selections are not possible. This ensures that users can only select one option from a group of related options.

Tag

jQuery Radio Buttons