How to implement picture scaling in C #

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Here are three simple ways to do this, and the next two methods are extensions, which are estimated to be useful sometimes
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<summary>
Shrink picture
</summary>
<param name= "Stroldpic" > Source Map file name (including path) </param>
<param name= "Strnewpic" > Save as File name (including path) </param>
<param name= "Intwidth" > Narrow to width </param>
<param name= "Intheight" > Shrink to Height </param>
public void Smallpic (string stroldpic, string strnewpic, int intwidth, int intheight)
{

System.Drawing.Bitmap Objpic,objnewpic;
Try
{
Objpic = new System.Drawing.Bitmap (stroldpic);
Objnewpic=new System.Drawing.Bitmap (objpic,intwidth,intheight);
Objnewpic.save (Strnewpic);

}
catch (Exception exp) {throw exp;}
Finally
{
Objpic=null;
Objnewpic=null;
}
}

<summary>
Shrink the picture proportionally, calculate the height automatically
</summary>
<param name= "Stroldpic" > Source Map file name (including path) </param>
<param name= "Strnewpic" > Save as File name (including path) </param>
<param name= "Intwidth" > Narrow to width </param>
public void Smallpic (string stroldpic, string strnewpic, int intwidth)
{

System.Drawing.Bitmap Objpic,objnewpic;
Try
{
Objpic = new System.Drawing.Bitmap (stroldpic);
int intheight= (intwidth/objpic.width) * objpic.height;
Objnewpic=new System.Drawing.Bitmap (objpic,intwidth,intheight);
Objnewpic.save (Strnewpic);

}
catch (Exception exp) {throw exp;}
Finally
{
Objpic=null;
Objnewpic=null;
}
}


<summary>
Shrink the picture proportionally, calculate the width automatically
</summary>
<param name= "Stroldpic" > Source Map file name (including path) </param>
<param name= "Strnewpic" > Save as File name (including path) </param>
<param name= "Intheight" > Shrink to Height </param>
public void Smallpic (string stroldpic, string strnewpic, int intheight)
{

System.Drawing.Bitmap Objpic,objnewpic;
Try
{
Objpic = new System.Drawing.Bitmap (stroldpic);
int intwidth= (intheight/objpic.height) * objpic.width;
Objnewpic=new System.Drawing.Bitmap (objpic,intwidth,intheight);
Objnewpic.save (Strnewpic);

}
catch (Exception exp) {throw exp;}
Finally
{
Objpic=null;
Objnewpic=null;
}
}