c# - How to trim a StringBuilder

Trim a StringBuilder

The StringBuilder class represents a mutable String of characters. The StringBuilder class cannot be inherited. The StringBuilder class represents a String-like object whose value is a mutable sequence of characters.

The following .net c# tutorial code demonstrates how we can trim a StringBuilder instance. In this .net c# tutorial code we will remove all the white spaces from starting and ending positions of a StringBuilder instance.

But there is no direct method in the StringBuilder class to trim an instance. So, at first, we have to convert a StringBuilder instance to a String object then we will call String Trim() method to trim the String object. Next, we will clear the StringBuilder instance and append the trimmed String object to the StringBuilder instance.

The StringBuilder ToString() method converts the value of a StringBuilder to a String. The StringBuilder ToString() method returns a string whose value is the same as this instance.

The String Trim() method removes all leading and trailing white-space characters from the current String. The String Trim() method returns the String that remains after all white-space characters are removed from the start and end of the current String. If no characters can be trimmed from the current instance then the method returns the current instance unchanged.

The StringBuilder Clear() method removes all characters from the current StringBuilder instance. The StringBuilder Clear() method returns a StringBuilder object whose length is zero.

The StringBuilder Append() method appends the String representation of a specified object to this instance. The StringBuilder Append(String) method overload appends a copy of the specified String to this instance.

Finally, we convert the StringBuilder instance to a String object by calling StringBuilder ToString() method. Then trim the String object by calling String Trim() method. Then clear the StringBuilder instance by calling StringBuilder Clear() method. Then we append the trimmed String object to the StringBuilder instance using the StringBuilder Append() method.

stringbuilder-trim.aspx


<%@ Page Language="C#" AutoEventWireup="true"%>
  
<!DOCTYPE html>
  
<script runat="server"> 
    protected void Button1_Click(object sender, System.EventArgs e)  
    {
        StringBuilder stringb = new StringBuilder();
        stringb.Append(" Blacksmith Plover. Ringed Plover. ");

        Label1.Text = "stringbuilder content: [" +stringb.ToString()+ "]";

        //this line trim stringbuilder contents.
        string trimmedString = stringb.ToString().Trim();

        stringb.Clear();
        stringb.Append(trimmedString);

        Label1.Text += "<br /><br />stringbuilder trimmed content: [" + stringb.ToString() + "]";
    }  
</script>  
  
<html xmlns="http://www.w3.org/1999/xhtml">  
<head id="Head1" runat="server">  
    <title>c# example - stringbuilder trim</title>  
</head>  
<body>  
    <form id="form1" runat="server">  
    <div>  
        <h2 style="color:MidnightBlue; font-style:italic;">  
            c# example - stringbuilder trim
        </h2>  
        <hr width="550" align="left" color="Gainsboro" />  
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            ID="Label1"   
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            Font-Size="Large"  
            >  
        </asp:Label>  
        <br /><br /><br />
        <asp:Button   
            ID="Button1"   
            runat="server"   
            Text="stringbuilder trim"  
            OnClick="Button1_Click"
            Height="40"  
            Font-Bold="true"  
            />  
    </div>  
    </form>  
</body>  
</html>

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