You cannot use block to hide table rows in Firefox or chrome.

You cannot use block to hide table rows in Firefox.

The following code can be executed normally in IE, but it is a bit abnormal in Firefox:
<Script language = "JavaScript">
Function testblack (tagname ){
VaR OBJ = Document. getelementbyid (tagname );
If (obj. style. Display = "Block "){
OBJ. style. Display = "NONE ";
} Else {
OBJ. style. Display = "Block ";
}
}
</SCRIPT>
<Table width = "760" border = "0" cellspacing = "0" cellpadding = "0">
<Tr onclick = "testblack ('divb ');">
<TD width = "760" Height = "20" bgcolor = "#00 CCFF"> click me! </TD>
</Tr>
<Tr id = "divb" style = "display: block;">
<TD width = "760" Height = "60" bgcolor = "# 9966ff"> </TD>
</Tr>
</Table>

Some netizens said that CSS may be unable to process tables. I personally think it is not because the above Code can be executed normally on IE; some netizens also said that the execution of "display: none;" was not recycled after "display: block;" opened page space was executed in Firefox, and "display: block;" was executed next time; "The display space will be re-created on the page, which is also untenable. The following code is normal for Firefox execution when used on Div:
<Script language = "JavaScript">
Function testblack (tagname ){
VaR OBJ = Document. getelementbyid (tagname );
If (obj. style. Display = "Block "){
OBJ. style. Display = "NONE ";
} Else {
OBJ. style. Display = "Block ";
}
}
</SCRIPT>
<Div style = "width: 760px; Height: 20px;" onclick = "testblack ('diva ');"> click me! </Div>
<Div id = "Diva" style = "width: 760px; Height: 60px; display: block;"> </div>

So far, we have not found a credible reason, but it does not mean that the table rows cannot be dynamically displayed/hidden in Firefox. display = ""; 'replaces 'style. display = "Block:
<Script language = "JavaScript">
Function testblack (tagname ){
VaR OBJ = Document. getelementbyid (tagname );
If (obj. style. Display = ""){
OBJ. style. Display = "NONE ";
} Else {
OBJ. style. Display = "";
}
}
</SCRIPT>
<Table width = "760" border = "0" cellspacing = "0" cellpadding = "0">
<Tr onclick = "testblack ('divc ');">
<TD width = "760" Height = "20" bgcolor = "#00 CCFF"> click me! </TD>
</Tr>
<Tr id = "divc">
<TD width = "760" Height = "60" bgcolor = "# 9966ff"> </TD>
</Tr>
</Table>