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 &nbsp; &nbsp; &nbsp; Assuming that you don't care about IEEE notations like &quot;NaN&quot; or &quot;Infin-<br />
&nbsp; &nbsp; &nbsp; &nbsp;ity&quot;, you probably just want to use a regular expression.<br />
<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (/\D/) &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;{ print &quot;has nondigits\n&quot; }<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (/^\d+$/) &nbsp; &nbsp; &nbsp; &nbsp; { print &quot;is a whole number\n&quot; }<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (/^-?\d+$/) &nbsp; &nbsp; &nbsp; { print &quot;is an integer\n&quot; }<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (/^[+-]?\d+$/) &nbsp; &nbsp;{ print &quot;is a +/- integer\n&quot; }<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (/^-?\d+\.?\d*$/) { print &quot;is a real number\n&quot; }<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (/^-?(?:\d+(?:\.\d*)?|\.\d<wbr />+)$/) { print &quot;is a decimal number\n&quot; }<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; if (/^([+-]?)(?=\d|\.\d)\d*(\<wbr />.\d*)?([Ee<wbr />]([+-]?\d+<wbr />))?$/)<br />
&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;{ print &quot;a C float\n&quot; }<br />

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      Assuming that you don't care about IEEE notations like "NaN" or "Infin-
       ity", you probably just want to use a regular expression.

          if (/\D/)            { print "has nondigits\n" }
          if (/^\d+$/)         { print "is a whole number\n" }
          if (/^-?\d+$/)       { print "is an integer\n" }
          if (/^[+-]?\d+$/)    { print "is a +/- integer\n" }
          if (/^-?\d+\.?\d*$/) { print "is a real number\n" }
          if (/^-?(?:\d+(?:\.\d*)?|\.\d+)$/) { print "is a decimal number\n" }
          if (/^([+-]?)(?=\d|\.\d)\d*(\.\d*)?([Ee]([+-]?\d+))?$/)
                               { print "a C float\n" }


<div>
refer this<br />
<br />
<a href="http://www.c-sharpcorner.com/UploadFile/prasad_1/RegExpressionSample111172005040853AM/RegExpressionSample1.aspx" rel="ugc">http://www.c-sharpcorner.com/UploadFile/prasad_1/RegExpressionSample111172005040853AM/RegExpressionSample1.aspx</a>
</div>


refer this

http://www.c-sharpcorner.com/UploadFile/prasad_1/RegExpressionSample111172005040853AM/RegExpressionSample1.aspx [http://www.c-sharpcorner.com/UploadFile/prasad_1/RegExpressionSample111172005040853AM/RegExpressionSample1.aspx]

<div>
<div class="content wysiwyg-content">
The below only works if the number isn't negative or have decimals. &nbsp;How would I modify it to handle such?<br />
<br />
if (Regex.IsMatch(MyString, @&quot;^\d+$&quot;))<br />
&nbsp; Console.WriteLine(MyString<wbr /> + &quot;&nbsp;is numeric&quot;);
</div>
</div>


The below only works if the number isn't negative or have decimals.  How would I modify it to handle such?

if (Regex.IsMatch(MyString, @"^\d+$"))
  Console.WriteLine(MyString + " is numeric");

Regex for numeric check

C# is an object-oriented programming language created in conjunction with Microsoft’s .NET framework. Compilation is usually done into the Microsoft Intermediate Language (MSIL), which is then JIT-compiled to native code (and cached) during execution in the Common Language Runtime (CLR).