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URL SOURCE:   FILE SOURCE:

MATCH PATTERN:

REPLACEMENT PATTERN:

OPERATION: # # USE .NET FLAGS: i
x		 m
s		  Help SHOW MATCH ARRAY:    EXPLAIN:  OPTIMIZE:    SHOW CODE: PHP
ASP		 VB.NET
C#.NET		 Java
JS
DELIM: HIGHLIGHT MATCHES:      GEN SAMPLES:   
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PASSWORD RESTRICTIONS:

Allow only these characters:  (any character) [  ]
At Least  Total Characters
No More Than   Total Characters
At Least  Lowercase Characters (a-z)
At Least  Uppercase Characters (A-Z)
At Least  Numeric Characters (0-9)
At Least  Special Characters in [^a-zA-Z0-9] [  ]
Disallow sequential alphanumeric sequences of or more (i.e. 123... abc... ABC...)
Disallow repeating characters of or more (i.e. 11... aa... AA... %%...)

WORD LIST:



SOURCE TEXT:

HIGHLIGHTED MATCHES:

Select All (to copy etc.)
CAPTURE GROUPS Help
0

"tom & jill" should become "tom & jill"


"tom & jill" should remain "tom & jill"


"tom € jill" should remain "tom € jill"


"tom <&> jill" should become "tom <&amp;> jill"


"tom &quot;&&quot; jill" should become "tom &quot;&amp;&quot; jill"

RESULTS:

Select All (to copy etc.)
Execution Time(sec.):
0.000010

Raw Match Pattern:
&(?![^& ]+;)

Raw Replace Pattern:
&amp;

C#.NET Code Example:
using System;
using System.Text.RegularExpressions;
namespace myapp
{
  class Class1
    {
      static void Main(string[] args)
        {
          String sourcestring = "source string to match with pattern";
          String matchpattern = @"&(?![^& ]+;)";
          String replacementpattern = @"&amp;";
          Console.WriteLine(Regex.Replace(sourcestring,matchpattern,replacementpattern));
        }
    }
}

$sourcestring after replacement:
"tom &amp; jill" should become "tom &amp; jill"


"tom &amp; jill" should remain "tom &amp; jill"


"tom &euro; jill" should remain "tom &euro; jill"


"tom <&amp;> jill" should become "tom <&amp;> jill"


"tom &quot;&amp;&quot; jill" should become "tom &quot;&amp;&quot; jill"