Simplified element writing (moved WriteElement(XmlTextWriter) out to

SvgDocument as Write(XmlTextWriter); allowed elements to decide whether or
not they should be written. E.g. text elements should not be written
unless they have children.

Source/Document Structure/SvgFragment.cs

 using System;
 using System.Drawing;
 using System.Drawing.Drawing2D;
+using System.Xml;
 
 namespace Svg
 {
@@ -41,7 +42,7 @@ namespace Svg
 
         private SvgUnit _x;
         private SvgUnit _y;
-        
+
         /// <summary>
         /// Gets or sets the position where the left point of the svg should start.
         /// </summary>
@@ -51,10 +52,10 @@ namespace Svg
             get { return _x; }
             set
             {
-                if(_x != value)
+                if (_x != value)
                 {
                     _x = value;
-                    OnAttributeChanged(new AttributeEventArgs{ Attribute = "x", Value = value });
+                    OnAttributeChanged(new AttributeEventArgs { Attribute = "x", Value = value });
                 }
             }
         }
@@ -68,10 +69,10 @@ namespace Svg
             get { return _y; }
             set
             {
-                if(_y != value)
+                if (_y != value)
                 {
                     _y = value;
-                    OnAttributeChanged(new AttributeEventArgs{ Attribute = "y", Value = value });
+                    OnAttributeChanged(new AttributeEventArgs { Attribute = "y", Value = value });
                 }
             }
         }
@@ -115,7 +116,7 @@ namespace Svg
             get { return this.Attributes.GetAttribute<SvgViewBox>("viewBox"); }
             set { this.Attributes["viewBox"] = value; }
         }
-        
+
         /// <summary>
         /// Gets or sets the aspect of the viewport.
         /// </summary>
@@ -185,29 +186,29 @@ namespace Svg
                     break;
             }
         }
-        
+
         /// <summary>
         /// Gets the <see cref="GraphicsPath"/> for this element.
         /// </summary>
         /// <value></value>
         public GraphicsPath Path
         {
-            get 
-            { 
+            get
+            {
                 var path = new GraphicsPath();
 
                 AddPaths(this, path);
-  
+
                 return path;
             }
         }
-        
+
         /// <summary>
         /// Gets the bounds of the svg element.
         /// </summary>
         /// <value>The bounds.</value>
-        public RectangleF Bounds 
-        { 
+        public RectangleF Bounds
+        {
             get
             {
                 return this.Path.GetBounds();
@@ -246,7 +247,7 @@ namespace Svg
                 }
             }
 
-            if (isWidthperc) 
+            if (isWidthperc)
             {
                 w = (bounds.Width + bounds.X) * (Width.Value * 0.01f);
             }
@@ -254,11 +255,11 @@ namespace Svg
             {
                 w = Width.ToDeviceValue(null, UnitRenderingType.Horizontal, this);
             }
-            if (isHeightperc) 
+            if (isHeightperc)
             {
                 h = (bounds.Height + bounds.Y) * (Height.Value * 0.01f);
             }
-            else 
+            else
             {
                 h = Height.ToDeviceValue(null, UnitRenderingType.Vertical, this);
             }
@@ -282,6 +283,20 @@ namespace Svg
             return newObj;
         }
 
+        //Override the default behavior, writing out the namespaces.
+        protected override void WriteStartElement(XmlTextWriter writer)
+        {
+            base.WriteStartElement(writer);
 
+            foreach (var ns in SvgAttributeAttribute.Namespaces)
+            {
+                if (string.IsNullOrEmpty(ns.Key))
+                    writer.WriteAttributeString("xmlns", ns.Value);
+                else
+                    writer.WriteAttributeString("xmlns:" + ns.Key, ns.Value);
+            }
+
+            writer.WriteAttributeString("version", "1.1");
+        }
     }
 }
\ No newline at end of file

Source/SvgDocument.cs

@@ -11,6 +11,8 @@ using System.Xml;
 using System.Linq;
 using ExCSS;
 using Svg.Css;
+using System.Threading;
+using System.Globalization;
 
 namespace Svg
 {
@@ -488,6 +490,18 @@ namespace Svg
             //Trace.TraceInformation("End Render");
         }
 
+        public override void Write(XmlTextWriter writer)
+        {
+            //Save previous culture and switch to invariant for writing
+            var previousCulture = Thread.CurrentThread.CurrentCulture;
+            Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;
+
+            base.Write(writer);
+
+            //Switch culture back
+            Thread.CurrentThread.CurrentCulture = previousCulture;
+        }
+
         public void Write(Stream stream)
         {
 
@@ -499,7 +513,7 @@ namespace Svg
             if (!String.IsNullOrEmpty(this.ExternalCSSHref))
                 xmlWriter.WriteProcessingInstruction("xml-stylesheet", String.Format("type=\"text/css\" href=\"{0}\"", this.ExternalCSSHref));
 
-            this.WriteElement(xmlWriter);
+            this.Write(xmlWriter);
 
             xmlWriter.Flush();
         }

Source/SvgElement.cs

@@ -520,16 +520,11 @@ namespace Svg
             this.Render(renderer);
         }
 
-        public void WriteElement(XmlTextWriter writer)
+        /// <summary>Derrived classes may decide that the element should not be written. For example, the text element shouldn't be written if it's empty.</summary>
+        public virtual bool ShouldWriteElement()
         {
-            //Save previous culture and switch to invariant for writing
-            var previousCulture = Thread.CurrentThread.CurrentCulture;
-            Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;
-
-            this.Write(writer);
-
-            //Switch culture back
-            Thread.CurrentThread.CurrentCulture = previousCulture;
+            //Write any element who has a name.
+            return (this.ElementName != String.Empty);
         }
 
         protected virtual void WriteStartElement(XmlTextWriter writer)
@@ -537,18 +532,8 @@ namespace Svg
             if (this.ElementName != String.Empty)
             {
                 writer.WriteStartElement(this.ElementName);
-                if (this.ElementName == "svg")
-                {
-					foreach (var ns in SvgAttributeAttribute.Namespaces)
-					{
-						if (string.IsNullOrEmpty(ns.Key))
-							writer.WriteAttributeString("xmlns", ns.Value);
-						else
-							writer.WriteAttributeString("xmlns:" + ns.Key, ns.Value);
-					}
-					writer.WriteAttributeString("version", "1.1");
-				}
             }
+
             this.WriteAttributes(writer);
         }
 
@@ -575,7 +560,8 @@ namespace Svg
 
                     forceWrite = false;
                     writeStyle = (attr.Attribute.Name == "fill");
-                    if ((attr.Attribute.Name == "fill") && (Parent != null))
+
+                    if (writeStyle && (Parent != null))
                     {
                     	if(propertyValue == SvgColourServer.NotSet) continue;
                     	
@@ -676,9 +662,9 @@ namespace Svg
             return resolved;
         }
 
-        protected virtual void Write(XmlTextWriter writer)
+        public virtual void Write(XmlTextWriter writer)
         {
-            if (this.ElementName != String.Empty)
+            if (ShouldWriteElement())
             {
                 this.WriteStartElement(writer);
                 this.WriteChildren(writer);

Source/SvgExtentions.cs

@@ -54,7 +54,7 @@ namespace Svg
             {
                 using (XmlTextWriter xml = new XmlTextWriter(str))
                 {
-                    elem.WriteElement(xml);
+                    elem.Write(xml);
                     result = str.ToString();
 
                 }

Source/Text/SvgTextBase.cs

@@ -19,7 +19,7 @@ namespace Svg
         protected SvgUnitCollection _dx = new SvgUnitCollection();
         private string _rotate;
         private List<float> _rotations = new List<float>();
-        
+
         /// <summary>
         /// Gets or sets the text to be rendered.
         /// </summary>
@@ -143,7 +143,7 @@ namespace Svg
                 {
                     this._rotate = value;
                     this._rotations.Clear();
-                    this._rotations.AddRange(from r in _rotate.Split(new char[] {',', ' ', '\r', '\n', '\t'}, StringSplitOptions.RemoveEmptyEntries) select float.Parse(r));
+                    this._rotations.AddRange(from r in _rotate.Split(new char[] { ',', ' ', '\r', '\n', '\t' }, StringSplitOptions.RemoveEmptyEntries) select float.Parse(r));
                     this.IsPathDirty = true;
                     OnAttributeChanged(new AttributeEventArgs { Attribute = "rotate", Value = value });
                 }
@@ -230,14 +230,14 @@ namespace Svg
         /// <value>The bounds.</value>
         public override System.Drawing.RectangleF Bounds
         {
-            get 
+            get
             {
                 var path = this.Path(null);
                 foreach (var elem in this.Children.OfType<SvgVisualElement>())
                 {
                     path.AddPath(elem.Path(null), false);
                 }
-                return path.GetBounds(); 
+                return path.GetBounds();
             }
         }
 
@@ -296,9 +296,9 @@ namespace Svg
         public override GraphicsPath Path(ISvgRenderer renderer)
         {
             //if there is a TSpan inside of this text element then path should not be null (even if this text is empty!)
-            var nodes = GetContentNodes().Where(x => x is SvgContentNode && 
-                                                     string.IsNullOrEmpty(x.Content.Trim(new[] {'\r', '\n', '\t'})));
-            
+            var nodes = GetContentNodes().Where(x => x is SvgContentNode &&
+                                                     string.IsNullOrEmpty(x.Content.Trim(new[] { '\r', '\n', '\t' })));
+
             if (_path == null || IsPathDirty || nodes.Count() == 1)
             {
                 renderer = (renderer ?? SvgRenderer.FromNull());
@@ -913,5 +913,10 @@ namespace Svg
             }
         }
 
+        /// <summary>Empty text elements are not legal - only write this element if it has children.</summary>
+        public override bool ShouldWriteElement()
+        {
+            return (this.HasChildren() || this.Nodes.Count > 0);
+        }
     }
 }