| 1 | <HTML>
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| 2 | <!-- This file is part of the HTML Reference Library ('HTMLib') -->
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| 3 | <!-- It should not be used outside of the HTMLib package -->
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| 4 | <!-- The HTMLib is © 1995-1998 Stephen Le Hunte -->
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| 5 | <!-- htmlib@htmlib.demon.co.uk -->
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| 6 | <HEAD>
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| 7 | <LINK REL="stylesheet" HREF="../style.css" TYPE="text/css">
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| 8 | <TITLE>The All collection</TITLE>
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| 9 | </HEAD>
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| 10 | <BODY TOPMARGIN="0" BGCOLOR="#FFFFE0" TEXT="#000000">
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| 11 |
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| 12 | <CENTER>
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| 13 | <SPAN CLASS="NSRtitle">The All Collection</SPAN>
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| 14 | </CENTER>
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| 15 |
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| 16 | <P><STRONG><EM>Note : </EM></STRONG>The All collection is <STRONG>Internet Explorer</STRONG> 4.0 specific. As <STRONG>Netscape</STRONG> doesn't support scripting for <EM>every</EM> HTML element, it doesn't support the All collection.
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| 17 |
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| 18 | <P>The All collection is an ordered, indexed array, containing a reference to every opening HTML element in a document. For example, consider the following document:
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| 19 |
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| 20 | <SPAN CLASS="egcode">
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| 21 | <BLOCKQUOTE>
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| 22 | <CODE><HTML><BR>
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| 23 | <HEAD><BR>
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| 24 | <TITLE>Test Document</TITLE><BR>
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| 25 | </HEAD><BR>
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| 26 | <BODY><BR>
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| 27 | <P>This is a test<BR>
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| 28 | <HR><BR>
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| 29 | </BODY><BR>
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| 30 | </HTML>
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| 31 | </CODE>
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| 32 | </BLOCKQUOTE>
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| 33 | </SPAN>
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| 34 |
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| 35 | <P>The all collection would be indexed from 0 to 5, with the elements being positioned:
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| 36 |
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| 37 | <P>
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| 38 | <TABLE WIDTH="60%">
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| 39 | <COLGROUP SPAN="2" ALIGN="center">
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| 40 | <TR>
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| 41 | <TD><STRONG>Element</STRONG></TD>
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| 42 | <TD><STRONG>All index</STRONG></TD>
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| 43 | </TR>
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| 44 | <TR>
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| 45 | <TD><CODE><HTML></CODE></TD>
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| 46 | <TD>0</TD>
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| 47 | </TR>
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| 48 | <TR>
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| 49 | <TD><CODE><HEAD></CODE></TD>
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| 50 | <TD>1</TD>
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| 51 | </TR>
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| 52 | <TR>
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| 53 | <TD><CODE><TITLE></CODE></TD>
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| 54 | <TD>2</TD>
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| 55 | </TR>
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| 56 | <TR>
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| 57 | <TD><CODE><BODY></CODE></TD>
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| 58 | <TD>3</TD>
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| 59 | </TR>
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| 60 | <TR>
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| 61 | <TD><CODE><P></CODE></TD>
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| 62 | <TD>4</TD>
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| 63 | </TR>
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| 64 | <TR>
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| 65 | <TD><CODE><HR></CODE></TD>
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| 66 | <TD>5</TD>
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| 67 | </TR>
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| 68 | </TABLE>
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| 69 |
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| 70 | <P>Element Object would normally be retrieved by their index in the All collection (for example, above <CODE>document.all(3)</CODE> contains a reference to the <CODE><BODY></CODE> element), but a string value can be used, as long as that string is a valid identifier (<CODE>ID</CODE> attribute value) for an element in the document.
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| 71 |
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| 72 | <P>E.g., changing the above example to:
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| 73 |
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| 74 | <SPAN CLASS="egcode">
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| 75 | <BLOCKQUOTE>
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| 76 | <CODE><HTML><BR>
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| 77 | <HEAD><BR>
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| 78 | <TITLE ID="Title1">Test Document</TITLE><BR>
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| 79 | </HEAD><BR>
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| 80 | <BODY><BR>
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| 81 | <P>This is a test<BR>
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| 82 | <HR><BR>
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| 83 | </BODY><BR>
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| 84 | </HTML>
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| 85 | </CODE>
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| 86 | </BLOCKQUOTE>
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| 87 | </SPAN>
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| 88 |
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| 89 | <P>...would mean that <CODE>document.all('Title1')</CODE> would be a reference to the <CODE><TITLE></CODE> element (whose <CODE>ID</CODE> is 'Title1'). This would be the same as <CODE>document.all(2)</CODE>. Note that it is also equivalent to using <CODE>document.all.item('Title1')</CODE> (see the item method below).
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| 90 |
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| 91 | <P><STRONG><EM>Note : </EM></STRONG>The All collection <STRONG>always</STRONG> includes a reference to <CODE><HTML></CODE>, <CODE><HEAD></CODE> and <CODE><BODY></CODE> elements, whether they exist in the document or not.
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| 92 |
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| 93 | <P><A NAME="properties"><STRONG>Properties</STRONG></A><BR>
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| 94 |
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| 95 | <P><SPAN CLASS="attr">length</SPAN><BR>
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| 96 | The <CODE>length</CODE> property returns the number of elements in the collection. Note that the <CODE>length</CODE> count starts at 1, not 0 as the all collection index does. Therefore, the <CODE>length</CODE> property may return a value of 5, but to access the 3rd element, you'd need to use <CODE>document.all(2).<EM>property</EM></CODE>
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| 97 |
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| 98 | <P><A NAME="methods"><STRONG>Methods</STRONG></A>
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| 99 |
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| 100 | <P><SPAN CLASS="attr">item</SPAN><BR>
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| 101 | The <CODE>item</CODE> method retrieves single items, or sub-collections from the all collection. It accepts the following arguments:
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| 102 |
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| 103 | <BLOCKQUOTE><EM>all</EM>.<STRONG>item</STRONG><EM>(index, sub-index)</EM>
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| 104 | </BLOCKQUOTE>
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| 105 |
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| 106 | <P>If <CODE>index</CODE> is a number, then the method returns a reference to the element object at that position in the all collections index. I.e. (using the example above)
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| 107 |
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| 108 | <SPAN CLASS="egcode">
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| 109 | <BLOCKQUOTE>
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| 110 | <CODE>strTag=document.all.item(2).tagName
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| 111 | </CODE>
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| 112 | </BLOCKQUOTE>
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| 113 | </SPAN>
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| 114 |
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| 115 | <P>would make <CODE>strTag</CODE> be <CODE>TITLE</CODE> - the value of the <CODE><TITLE></CODE> elements <CODE>tagName</CODE> property. As you can see, this is effectively the long-hand version of using <CODE>document.all(2).<EM>property</EM></CODE>.
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| 116 |
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| 117 | <P>If the <CODE>index</CODE> property is a string value, then the <CODE>item</CODE> method returns a sub-collection, containing a reference to every element in the document that has its <CODE>ID</CODE> or <CODE>NAME</CODE> attribute set to the string contained in the <CODE>index</CODE> argument. To retrieve certain element objects from this sub-collection, the <CODE>sub-index</CODE> argument must be used. For example, assume that 5 elements in a document all have the <CODE>NAME</CODE> attribute set as <CODE>radColour</CODE> (these imaginary elements are radio buttons). To interrogate the 3rd of these elements, you could use:
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| 118 |
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| 119 | <SPAN CLASS="egcode">
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| 120 | <BLOCKQUOTE>
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| 121 | <CODE>strThird=document.all('radColour',2).<EM>propertyName</EM>
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| 122 | </CODE>
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| 123 | </BLOCKQUOTE>
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| 124 | </SPAN>
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| 125 |
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| 126 | <P><A NAME="methtags"><SPAN CLASS="attr">tags</SPAN></A><BR>
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| 127 | The <CODE>tags</CODE> method returns a collection of element objects whose <CODE>tagName</CODE> property is the same as the <CODE>tag</CODE> argument used for the method. This differs from the <CODE>item</CODE> property in that that interrogates <CODE>ID</CODE> and <CODE>NAME</CODE> values if necessary.
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| 128 |
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| 129 | <SPAN CLASS="egcode">
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| 130 | <BLOCKQUOTE>
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| 131 | <CODE>document.all.tags('EM')
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| 132 | </CODE>
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| 133 | </BLOCKQUOTE>
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| 134 | </SPAN>
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| 135 |
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| 136 | <P>would return a collection of all the <CODE><EM></CODE> objects in the document.
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| 137 |
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| 138 |
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| 139 | <P>
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| 140 | <P ALIGN="right" CLASS="copyright">© 1995-1998, Stephen Le Hunte</P>
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| 141 | </BODY>
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| 142 | </HTML>
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