Question

I’ve been trying to highlight a search result in DataTable. First, I loop through rows of DataTable and call a function to look for a matched keyword to highlight those words, then update DataTable row with a new string with highlighted keywords.

I bind the DataTable dtResult to the DataList. It worked fine until I added this code block to SearchDemo function to highlight the keyword :

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    For i = 0 To dtResult.Rows.Count - 1 Step 1          Dim strTemp As String = dtResult.Rows(i).ToString         strVerse = blHelper.Highlight(s, strTemp)         dtResult.Rows(i)('verse') = strVerse     Next 

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A Label inside the DataList bound this ‘verse’ column shows System.Data.DataRow. The rest shows the correct data.

Please see the following code block :

…………………….

Public Shared Function SearchDemo(ByVal s As String) As DataTable      Dim dtResult As New DataTable      dtResult = SearchDetail(s)       Dim i As Integer = dtResult.Rows.Count      For i = 0 To dtResult.Rows.Count - 1 Step 1          Dim strTemp As String = dtResult.Rows(i).ToString         strVerse = blHelper.Highlight(s, strTemp)         dtResult.Rows(i)('verse') = strVerse      Next      Return dtResult End Function 

…………………………………………………

These two functions below works fine.

    'Highlight the keywords in the returned result  Public Shared Function Highlight(ByVal Search_Str As String, ByVal InputTxt As String) As String      ' Setup the regular expression and add the Or operator.     Dim RegExp As Regex = New Regex(Search_Str.Replace(' ', '|').Trim(), RegexOptions.IgnoreCase)      ' Highlight keywords by calling the MatchEvaluator delegate each time a keyword is found.     Highlight = RegExp.Replace(InputTxt, New MatchEvaluator(AddressOf ReplaceKeyWords))      ' Set the Regex to nothing.     RegExp = Nothing  End Function  Public Shared Function ReplaceKeyWords(ByVal m As Match) As String      Return '<b>' & m.Value & '</b>'  End Function 

Every other rows of the DataTable dtResul are shown properly except the rows of column ‘verse’ that I tried to highlight the keywords. If I remove a loop (to highlight keywords) inside the SearchDemo, it will works fine. Can anyone have a look at these codes and point me to the right direction please ?

Answer 1

Your input text is dtResult.Rows(i).ToString which is ‘System.Data.DataRow’.

Change this line:

Dim strTemp As String = dtResult.Rows(i).ToString 

To:

Dim strTemp As String = dtResult.Rows(i)('verse').ToString