Was this page helpful?
Your feedback about this content is important. Let us know what you think.
Additional feedback?
1500 characters remaining
Export (0) Print
Expand All

String.IndexOfAny Method (Char[])

Reports the zero-based index of the first occurrence in this instance of any character in a specified array of Unicode characters.

Namespace:  System
Assembly:  mscorlib (in mscorlib.dll)

public int IndexOfAny(
	char[] anyOf
)

Parameters

anyOf
Type: System.Char[]

A Unicode character array containing one or more characters to seek.

Return Value

Type: System.Int32
The zero-based index position of the first occurrence in this instance where any character in anyOf was found; -1 if no character in anyOf was found.

ExceptionCondition
ArgumentNullException

anyOf is null.

Index numbering starts from zero.

The search for anyOf is case-sensitive.

This method performs an ordinal (culture-insensitive) search, where a character is considered equivalent to another character only if their Unicode scalar value are the same. To perform a culture-sensitive search, use the CompareInfo.IndexOf method, where a Unicode scalar value representing a precomposed character, such as the ligature "Æ" (U+00C6), might be considered equivalent to any occurrence of the character's components in the correct sequence, such as "AE" (U+0041, U+0045), depending on the culture.

The following example uses the IndexOfAny method to check for invalid characters in a user entered string.

/* Get the tree node under the mouse pointer and 
   save it in the mySelectedNode variable. */ 
private void treeView1_MouseDown(object sender, 
  System.Windows.Forms.MouseEventArgs e)
{
   mySelectedNode = treeView1.GetNodeAt(e.X, e.Y);
}

private void menuItem1_Click(object sender, System.EventArgs e)
{
   if (mySelectedNode != null && mySelectedNode.Parent != null)
   {
      treeView1.SelectedNode = mySelectedNode;
      treeView1.LabelEdit = true;
      if(!mySelectedNode.IsEditing)
      {
         mySelectedNode.BeginEdit();
      }
   }
   else
   {
      MessageBox.Show("No tree node selected or selected node is a root node.\n" + 
         "Editing of root nodes is not allowed.", "Invalid selection");
   }
}

private void treeView1_AfterLabelEdit(object sender, 
         System.Windows.Forms.NodeLabelEditEventArgs e)
{
   if (e.Label != null)
   {
     if(e.Label.Length > 0)
     {
        if (e.Label.IndexOfAny(new char[]{'@', '.', ',', '!'}) == -1)
        {
           // Stop editing without canceling the label change.
           e.Node.EndEdit(false);
        }
        else
        {
           /* Cancel the label edit action, inform the user, and 
              place the node in edit mode again. */
           e.CancelEdit = true;
           MessageBox.Show("Invalid tree node label.\n" + 
              "The invalid characters are: '@','.', ',', '!'", 
              "Node Label Edit");
           e.Node.BeginEdit();
        }
     }
     else
     {
        /* Cancel the label edit action, inform the user, and 
           place the node in edit mode again. */
        e.CancelEdit = true;
        MessageBox.Show("Invalid tree node label.\nThe label cannot be blank", 
           "Node Label Edit");
        e.Node.BeginEdit();
     }
   }
}

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
Show:
© 2015 Microsoft