My Code:
DataTable dt = fs.DataTable;
int columnsNumber = dt.Columns.Count;
string[] array = new string[columnsNumber];
for (int k=0; k==columnsNumber; k++)
{
array[k] = dt.Columns[k].ColumnName;
}
foreach (var item in array)
{
MessageBox.Show(item);
}
MessageBox has displaying the blank message.
If I have run this code, no problem;
array[1] = dt.Columns[1].ColumnName;
array[2] = dt.Columns[2].ColumnName;
array[3] = dt.Columns[3].ColumnName;
This work. What is the problem ?
Your cicle just checking k==kolonSayisi :
for (int k=0; k==kolonSayisi; k++)
{
array[k] = dt.Columns[k].ColumnName;
}
I think you should write it like this:
for (int k=0; k < columnsNumber; k++)
{
array[k] = dt.Columns[k].ColumnName;
}
You have included a ==
operator in for loop
where you should be using <
Change
for (int k=0; k==kolonSayisi; k++)
to
for (int k=0; k<kolonSayisi; k++)
You can also use this way
var listToArray = new listToArray<string>();
foreach (DataColumn dataCol in dt.Columns)
listToArray.Add(dataCol.ColumnName);
listToArray.ToArray();
Hope it helps.
You can use like this:
DataTable table = new DataTable();
table.Columns.Add("col1");
table.Columns.Add("col2");
table.Columns.Add("col3");
var array = table.Columns
.Cast<DataColumn>()
.Select(c => c.ColumnName)
.ToArray();
foreach(var item in array)
{
MessageBox.Show(item);
}
A for loop works the following way:
In the parentheses the first part defines a counting or increment variable and sets the starting value. The second part is the cancel condition. You can read it like: if condition is false then stop the loop. The third part defines the step size, how you want to increment your variable.
Now if you look at your condition k==columnsNumber
you are trying to check if k equals the number. In the first iteration where k is 0 it will return false if columnsNumber
is not 0. So your loop will stop.
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