How to determine if string contains specific substring within the first X characters

Question

I want to check whether Value1 below contains  abc  within the first X characters  How would you check this with an if statement   var Value1    ddabcgghh    if  Value1 Contains  abc          found   true      It could be within the first 3  4 or 5 characters

User · Answer

shorter version   found   Value1 StartsWith  abc      sorry  but I am a stickler for  less  code     Given the edit of the questioner I would actually go with something that accepted an offset  this may in fact be a Great place to an Extension method that overloads StartsWith  public static class StackOverflowExtensions       public static bool StartsWith this String val  string findString  int count                return val Substring 0  count  Contains findString

User · Answer

This is what you need     if  Value1 StartsWith  abc      found   true

User · Answer

Use IndexOf is easier and high performance   int index   Value1 IndexOf  abc    bool found   index  gt   0  amp  amp  index  lt  x

User · Answer

if  Value1 StartsWith  abc      found   true

User · Answer

You can also use regular expressions  less readable though   string regex       0 7 abc    System Text RegularExpressions Regex reg   new System Text RegularExpressions Regex regex   string Value1    sssddabcgghh    Console WriteLine reg Match Value1  Success

User · Answer

shorter version   found   Value1 StartsWith  abc      sorry  but I am a stickler for  less  code     Given the edit of the questioner I would actually go with something that accepted an offset  this may in fact be a Great place to an Extension method that overloads StartsWith  public static class StackOverflowExtensions       public static bool StartsWith this String val  string findString  int count                return val Substring 0  count  Contains findString

User · Answer

shorter version   found   Value1 StartsWith  abc      sorry  but I am a stickler for  less  code     Given the edit of the questioner I would actually go with something that accepted an offset  this may in fact be a Great place to an Extension method that overloads StartsWith  public static class StackOverflowExtensions       public static bool StartsWith this String val  string findString  int count                return val Substring 0  count  Contains findString

User · Answer

if  Value1 StartsWith  abc      found   true

User · Answer

Use IndexOf is easier and high performance   int index   Value1 IndexOf  abc    bool found   index  gt   0  amp  amp  index  lt  x

User · Answer

Use IndexOf is easier and high performance   int index   Value1 IndexOf  abc    bool found   index  gt   0  amp  amp  index  lt  x

User · Answer

if  Value1 StartsWith  abc      found   true

User · Answer

You re close    but use  if  Value1 StartsWith  abc

User · Answer

This is what you need     if  Value1 StartsWith  abc      found   true

User · Answer

I would use one of the of the overloads of the IndexOf method  bool found   Value1 IndexOf  abc   0  7     -1

User · Answer

A more explicit version is  found   Value1 StartsWith  abc   StringComparison Ordinal     It s best to always explicitly list the particular comparison you are doing   The String class can be somewhat inconsistent with the type of comparisons that are used

User · Answer

A more explicit version is  found   Value1 StartsWith  abc   StringComparison Ordinal     It s best to always explicitly list the particular comparison you are doing   The String class can be somewhat inconsistent with the type of comparisons that are used

User · Answer

if  Value1 StartsWith  abc      found   true

User · Answer

A more explicit version is  found   Value1 StartsWith  abc   StringComparison Ordinal     It s best to always explicitly list the particular comparison you are doing   The String class can be somewhat inconsistent with the type of comparisons that are used

User · Answer

You re close    but use  if  Value1 StartsWith  abc

User · Answer

You can also use regular expressions  less readable though   string regex       0 7 abc    System Text RegularExpressions Regex reg   new System Text RegularExpressions Regex regex   string Value1    sssddabcgghh    Console WriteLine reg Match Value1  Success

User · Answer

Or if you need to set the value of found   found   Value1 StartsWith  abc     Edit  Given your edit  I would do something like   found   Value1 Substring 0  5  Contains  abc

User · Answer

Adding on from the answer below i have created this method       public static bool ContainsInvalidStrings IList lt string gt  invalidStrings string stringToCheck                 foreach  string invalidString in invalidStrings                        var index   stringToCheck IndexOf invalidString  StringComparison InvariantCultureIgnoreCase               if  index    -1                                return true                                  return false          it can be used like this               var unsupportedTypes   new List lt string gt                           POINT Empty                MULTIPOINT                MULTILINESTRING                MULTIPOLYGON                GEOMETRYCOLLECTION                CIRCULARSTRING                COMPOUNDCURVE                CURVEPOLYGON                MULTICURVE                TRIANGLE                TIN                POLYHEDRALSURFACE                           bool hasInvalidValues     ContainsInvalidStrings unsupportedTypes possibleWKT     you can check for multiple invalid values this way

User · Answer

Or if you need to set the value of found   found   Value1 StartsWith  abc     Edit  Given your edit  I would do something like   found   Value1 Substring 0  5  Contains  abc

User · Answer

You can also use regular expressions  less readable though   string regex       0 7 abc    System Text RegularExpressions Regex reg   new System Text RegularExpressions Regex regex   string Value1    sssddabcgghh    Console WriteLine reg Match Value1  Success

User · Answer

You can also use regular expressions  less readable though   string regex       0 7 abc    System Text RegularExpressions Regex reg   new System Text RegularExpressions Regex regex   string Value1    sssddabcgghh    Console WriteLine reg Match Value1  Success

User · Answer

I would use one of the of the overloads of the IndexOf method  bool found   Value1 IndexOf  abc   0  7     -1

User · Answer

Use IndexOf is easier and high performance   int index   Value1 IndexOf  abc    bool found   index  gt   0  amp  amp  index  lt  x

User · Answer

You re close    but use  if  Value1 StartsWith  abc

User · Answer

A more explicit version is  found   Value1 StartsWith  abc   StringComparison Ordinal     It s best to always explicitly list the particular comparison you are doing   The String class can be somewhat inconsistent with the type of comparisons that are used

User · Answer

This is what you need     if  Value1 StartsWith  abc      found   true

User · Answer

You re close    but use  if  Value1 StartsWith  abc

User · Answer

Or if you need to set the value of found   found   Value1 StartsWith  abc     Edit  Given your edit  I would do something like   found   Value1 Substring 0  5  Contains  abc

User · Answer

Adding on from the answer below i have created this method       public static bool ContainsInvalidStrings IList lt string gt  invalidStrings string stringToCheck                 foreach  string invalidString in invalidStrings                        var index   stringToCheck IndexOf invalidString  StringComparison InvariantCultureIgnoreCase               if  index    -1                                return true                                  return false          it can be used like this               var unsupportedTypes   new List lt string gt                           POINT Empty                MULTIPOINT                MULTILINESTRING                MULTIPOLYGON                GEOMETRYCOLLECTION                CIRCULARSTRING                COMPOUNDCURVE                CURVEPOLYGON                MULTICURVE                TRIANGLE                TIN                POLYHEDRALSURFACE                           bool hasInvalidValues     ContainsInvalidStrings unsupportedTypes possibleWKT     you can check for multiple invalid values this way

User · Answer

This is what you need     if  Value1 StartsWith  abc      found   true

User · Answer

shorter version   found   Value1 StartsWith  abc      sorry  but I am a stickler for  less  code     Given the edit of the questioner I would actually go with something that accepted an offset  this may in fact be a Great place to an Extension method that overloads StartsWith  public static class StackOverflowExtensions       public static bool StartsWith this String val  string findString  int count                return val Substring 0  count  Contains findString

User · Answer

Or if you need to set the value of found   found   Value1 StartsWith  abc     Edit  Given your edit  I would do something like   found   Value1 Substring 0  5  Contains  abc

[c#] How to determine if string contains specific substring within the first X characters

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