--- title: "How to Use JSON" description: "In this blog, I’m explaining the how get the in the JSON. Basically JSON is used for the read data from the web server and show the data in the web p" author: "Anchal Kesharwani" published: 2014-09-20 updated: 2014-09-20 canonical: https://www.mindstick.com/blog/693/how-to-use-json category: "json" tags: ["json"] reading_time: 3 minutes --- # How to Use JSON In this blog, I’m explaining the how get the in the JSON.\ Basically JSON is used for the read data from the [web server](https://www.mindstick.com/articles/23199/digital-personal-server-the-premium-web-server) and show the data in the [web page](https://www.mindstick.com/forum/718/sql-server-report-alignment-to-center-of-web-page). ##### There are two way to get the web server: ##### Use JSON.parse () The [JavaScript function](https://www.mindstick.com/forum/2090/send-data-from-asp-dot-net-code-behind-to-a-javascript-function) JSON.parse(text) can be used to convert a JSON text into a JavaScript object. Syntax JSON.parse(text , reviver) Where there [parameters](https://www.mindstick.com/articles/87/passing-parameters-in-c-sharp) are: text: The string to parse as JSON. See the [JSON object](https://www.mindstick.com/forum/699/how-to-parse-into-json-object-using-json-parse-in-node-js) for a description of JSON syntax. reviver: If a function, prescribes how the value originally produced by parsing is transformed, before being returned. This was the [optional parameter](https://www.mindstick.com/interview/1310/how-do-i-simulate-optional-parameters-to-com-calls). It returns object corresponding to the given JSON text. If the string parse is not valid it throws the exception. ##### JSON.parse () Example Here three student’s records as string that contain the JSON syntax. ```  var student='{"students":['+'{"name":"Ajay Mishra","age":21,"address":"Allahabad","phone":"121 1234567","email":"ajay@mail.com"},'+'{"name":"Satish Kumar","age":22,"address":"Allahabad","phone":"121 1234568","email":"satish@mail.com"},'+'{"name":"Sonu Sharma","age":21,"address":"Allahabad","phone":"121 1234569","email":"sonu@mail.com"}]}'; ``` JSON syntax is the JavaScript syntax. Use the JSON.parse() function is used for covert the JSON text into JavaScript object. ##### Example ```                                                  JSON.parse() Example                                                               

JSON.parse() Example

                               

                                                ``` This example output is given below. The object contain three student objects that contain records. ![How to Use JSON](https://www.mindstick.com/blogs/8f5245db-5aed-480a-80ed-26c796f09adb/images/4c837f4e-ca44-455e-a58e-0ded8a8aa8be.png) ##### Use eval () JSON.eval () function is also used for convert the JSON object JSON text to JavaScript object. Syntax ## JSON.eval (string); Where the parameter string is expression, statement, or sequence of statements. The expression can include variables and properties of existing objects. Let’s try this example with same student strings. ##### Example ```                                                  eval() Example                                                               

eval() Example

                               

                                                ``` The above example give the output same as JSON.parse() example but the eval() function can compile and execute any JavaScript. This represents a potential security problem. So it try to avoid it. ##### Differences between JSON.parse () vs eval() There are following differences between JSON.parse () and eval(): · JSON is just a subset of the JavaScript but the eval evaluated the JavaScript language and not just a subset. · JSON only allow to parse the JSON format data but eval accept any type of string. · Not all browser support the native JSON so there will be time to use the eval to the JSON string. · The eval function is very fast. However, it can compile and execute any JavaScript program, so there can be security issues. The use of eval is indicated when the source is trusted and competent. It is much safer to use a JSON parser. --- Original Source: https://www.mindstick.com/blog/693/how-to-use-json Copyright © MindStick Software Pvt. Ltd. This Markdown version is provided for developers, AI systems, and offline reading.