Question

Possible Duplicate:
C#: why does the string type have a .ToString() method

Why is there a ToString method exist in String class (VB.NET)?

String.ToString()

Will it be a overhead if it is used like

TextBox.Text.ToString()

Answer 1

The ToString method is found on Object from which String inherits. The implementation of Object.ToString is to print the typename.

public virtual string ToString() {
    return this.GetType().ToString();
} 

The type String overrides this method to return itself.

public override string ToString() {
    return this;
} 

The code TextBox.Text.ToString() has an unnecessary call to ToString, but it is unlikely that there will be any noticable performance impact from doing so.