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JavaScript Global method: parseFloat()

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The JavaScript Global parseFloat() parses a string and returns a floating point number, assuming that the string can be interpreted as such a number. It finds the first character after leading spaces, works out if this is one that can appear in a number and then continues parsing the string until it reaches the end of any part that is interpretable as a number, returning that number as a number value, not a string. If the first available non-space character is not numerical then the method returns NaN. Only the first of multiple numbers will be returned.

 

It has the following syntax with the following parameters:

 

parseFloat(x)

 

Parameter

Required / Optional

Description

x

Required

String forming the input parameter

 

EXAMPLE:


HTML USED IN THIS EXAMPLE:
<!DOCTYPE html>
<html> <!-- Copyright (c) Nematrian Limited 2018 -->
<head>
<style>
table,th,tr,td {border: 1px solid black; border-collapse :collapse;}
</style>
</head>
<body>
<table>
<tr>
<th>Example</th>
<th>Resulting value of <code>x</code></th>
</tr>
<tr>
<td><code id="Example"></code></td>
<td><code id="Result"></code></td>
</tr>
<tr>
<td><code id="Example2"></code></td>
<td><code id="Result2"></code></td>
</tr>
</table>

<script>
document.getElementById("Example").innerHTML =
  'var x = parseFloat("   3.4, 4.4");';
document.getElementById("Result").innerHTML =
  parseFloat("   3.4, 4.4");
document.getElementById("Example2").innerHTML =
  'var x2 = parseFloat("   a3.4, 4.4");';
document.getElementById("Result2").innerHTML =
  parseFloat("   a3.4, 4.4");
</script>

</body>
</html>

FUNCTION THAT MAY ASSIST IN TESTING WHETHER FEATURE IS SUPPORTED:
function isSupportedJavaScriptMethodGlobalParseFloat() {
  return (parseFloat("3.4") == 3.4);
}


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