I need to get a specific column header name based on value.
For ex: I am using the below query to get list of column headers and it works fine and on top of this can I get column names which has specific name like Department alone.
LINQ
string[] columnNames = dt.Columns.Cast<DataColumn>()
.Select(x => x.ColumnName)
.ToArray();
How can I add contains or exists to this query to get specific columns.
Simply add a filter, like this:
string[] columnNames = dt.Columns.Cast<DataColumn>()
.Select(x => x.ColumnName)
.Where(x => x == "Department")
.ToArray();
List<string> containsKeys = new List<string>();
containsKeys.Add("SomeWildCard");
DataTable dt = new DataTable();
string[] columnNames = dt.Columns.Cast<DataColumn>()
.Select(x => x.ColumnName)
.ToArray().Where(t => containsKeys.Contains(t)).ToArray();
You can either select then filter the result:
.Select(x => x.ColumnName).Where(c => c == "Department")
Or first filter then select:
.Where(x => x.ColumnName == "Department").Select(c => c.ColumnName)
Columns property is of type DataColumnCollection, which has an indexer public DataColumn this[string name] to get DataColumn by name:
DataColumn dc = dt.Columns["Department"];
to get multiple columns by name use Select() with indexer:
List<string> names = new List<string> { "Department", "Something" };
DataColumn[] columns = names.Select(name => dt.Columns[name]).ToArray();
.Where(x => x == "Department")?xisDataColumn. How is that possible? Probably you mean.Where(x => x.ColumnName == "Name"). Check my answer.Select. I didn't answer this question because it's unclear and rather pointless to select a single string from a list of strings when you already have the string. I wish other people had thought the same...WhereafterSelectit works and I also have pointed this. I thought you said replaceSelectwithWhere.