HTML Articles - Page 134 of 151

Use the document.embeds property in JavaScript to get the number of tags in a document.ExampleYou can try to run the following code to implement document.embeds property in JavaScript.Live Demo           JavaScript Example                              var num = document.embeds.length;          document.write("How many embed tags: "+num);          

To get the value of the type attribute of a link in JavaScript, use the type property. The type attribute is used to tell that the document is html (text/html) or css (text/css), etc.ExampleYou can try to run the following code to get the value of the type attribute of a link.Live Demo           Qries                var myVal = document.getElementById("anchorid").type;          document.write("Value of type attribute: "+myVal);          

If a semicolon is misplaced in JavaScript, then it may lead to misleading results. Let’s see an example, wherein the if statement condition is false, but due to misplaced semi-colon, the value gets printed.Example                    var val1 = 10;          if (val1 == 15) {             document.write("Prints due to misplaced semi-colon: "+val1);          }          var val2 = 10;          if (val2 == 15) {             // this won't get printed             document.write(val2);          }          

Yes, it is a good practice to place all the JavaScript declarations at the top. Let’s see an example −Example           JavaScript String match() Method                        // all the variables declared at top          var str, re, found;                    str = "For more information, see Chapter 3.4.5.1";          re = /(chapter \d+(\.\d)*)/i;          found = str.match( re );          document.write(found );           The following are the valid reasons −Gives a single place to check for all the variables.Helps in avoiding global variablesRe-declarations are avoided.The code is easy to read for others as well.

In this tutorial, we will learn how to display the selected option in a dropdown list with JavaScript. What is a dropdown list? A dropdown list is a switchable menu that enables users to select one item from various options. A drop-down list is generated with the tag is most frequently used in forms to gather user input. After submitting the form, the name attribute must refer to the form's data. The DOM API functions getElementById() and querySelector() can be used to choose a element. The process use the querySelector() function to first select the "button" and "select" ... Read More

To show all the options from a dropdown list, use the options property. The property allows you to get all the options with length property.ExampleYou can try to run the following code to get all the options from a drop-down list.Live Demo                                 One             Two             Three                                 Click the button to get all the options                function display() {             var a, i, options;             a = document.getElementById("selectNow");             options = "";             for (i = 0; i < a.length; i++) {                options = options + " " + a.options[i].text;             }             document.write("DropDown Options: "+options);          }          

The charCodeAt() method returns a number indicating the Unicode value of the character at the given index. Unicode code points range from 0 to 1, 114, 111. The first 128 Unicode code points are a direct match of the ASCII character encoding.The following parameter is supported by charCodeAt(index) −index − An integer between 0 and 1 less than the length of the string; if unspecified, defaults to 0.ExampleYou can try to run the following code to return a number indicating the Unicode value of the character −           JavaScript String charCodeAt() Method           ... Read More

Your server sends some data to the visitor's browser in the form of a cookie. The browser may accept the cookie. If it does, it is stored as a plain text record on the visitor's hard drive. Now, when the visitor arrives at another page on your site, the browser sends the same cookie to the server for retrieval. Once retrieved, your server knows/remembers what was stored earlier.Cookies are a plain text data record of 5 variable-length fields −Expires − The date the cookie will expire. If this is blank, the cookie will expire when the visitor quits the browser.Domain − The ... Read More

The toLocaleString() method returns a string value version of the current number in a format that may vary according to a browser's local settings.ExampleYou can try to run the following code to return a string value version −           JavaScript toLocaleString() Method                        var num = new Number(150.1234);          document.write( num.toLocaleString());          

Use the toExponential() method to force a number to display in exponential notation, even if the number is in the range in which JavaScript normally uses standard notation.The following is the parameter −fractionDigits - An integer specifying the number of digits after the decimal point. Defaults to as many digits as necessary to specify the number.ExampleYou can try to run the following code to force a number to display in exponential function −           Javascript Method toExponential()                        var num=77.1234;          var ... Read More