Assignment 13 - Simple Adder

LABAR Project 13

This assignment is to be done during your one hour lab by arrangement (LABAR). This assignment requires you to write your first javascript to declare, assign and display three variables of the string, number, and boolean types respectively.

In this assignment, Assignment #13, you are to create a simple addition only calculator as in the HTML Form below. This calculator can:

• provide the addition and clear javascript functions;
• provide two HTML text inputs for user to enter the two operaand numbers for addition function;
• provide a HTML text input for the onClick triggered math function to place the result (number);
• when add (+) operator button is pressed, i.e. the onClick event, the corresponding addition javascript function shall place the result in the Answer text Input;
• when the Clear "C" button is pressed, i.e. the onClick event, all text Input fields shall be cleared.

Enter a number:
Enter a number:

Answer =

The above html form code is listed below:

<FORM NAME="Calculator" METHOD="post"> <P>Enter a number: <INPUT TYPE=TEXT NAME="input_A" SIZE=10></P> <P>Enter a number: <INPUT TYPE=TEXT NAME="input_B" SIZE=10></P> <P><INPUT TYPE="button" VALUE="+" name="AddButton" onClick="CalculateSum(this.form.input_A.value, this.form.input_B.value, this.form)"> <INPUT TYPE="button" VALUE="C" name="ClearButton" onClick="ClearForm(this.form)"></P> <P>Answer = <INPUT TYPE=TEXT NAME="Answer" SIZE=12></P> </FORM>

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Sample Code:

Javascript Adder

 <SCRIPT type="text/javascript"> function CalculateSum(Atext, Btext, form){ var A = parseFloat(Atext); var B = parseFloat(Btext); form.Answer.value = A + B; } function ClearForm(form){ form.input_A.value = ""; form.input_B.value = ""; form.Answer.value = ""; } </SCRIPT> <P><FONT SIZE="+2">Simple Adder</FONT></P> <FORM NAME="Calculator" METHOD="post"> <P>Enter a number: <INPUT TYPE=TEXT NAME="input_A" SIZE=10></P> <P>Enter a number: <INPUT TYPE=TEXT NAME="input_B" SIZE=10></P> <P><INPUT TYPE="button" VALUE="Add Numbers" name="AddButton" onClick="CalculateSum(this.form.input_A.value, this.form.input_B.value, this.form)"></P> <P><INPUT TYPE="button" VALUE="Clear Fields" name="ClearButton" onClick="ClearForm(this.form)"></P> <P>Answer = <INPUT TYPE=TEXT NAME="Answer" SIZE=12></P> </FORM>

Try this adder out!

Simple Adder

Enter a number:
Enter a number:


Answer =