prepend

问题 I want to edit an entire mysql table's row. I don't really know mysql at all, so in basic programming this is what I want to do: from row year in table videos: The key here is that I want to prepend 19/20 and not add it. if (year < 50) year = year+2000 else year = year+1900 How would I go about doing this? 回答1: Try this: UPDATE yourtable SET year = year + IF(year >= 50, 1900, 2000) This will work both if your column is an integer type and also if it is a character type. 回答2: mysql> create

问题 What is the most efficient way to prepend std::string ? Is it worth writing out an entire function to do so, or would it take only 1 - 2 lines? I'm not seeing anything related to an std::string::push_front . 回答1: There actually is a similar function to the non-existing std::string::push_front , see the below example. Documentation of std::string::insert #include <iostream> #include <string> int main (int argc, char *argv[]) { std::string s1 (" world"); std::string s2 ("ello"); s1.insert (0,

问题 There is no big difference between those functions except the syntax: $('.target').append('text'); $('text').appendTo('.target'); As said in jQuery docs: The .append() and .appendTo() methods perform the same task. The major difference is in the syntax-specifically, in the placement of the content and target. With .append(), the selector expression preceding the method is the container into which the content is inserted. With .appendTo(), on the other hand, the content precedes the method,

问题 Imagine you have a file sink("example.txt") data.frame(a = runif(10), b = runif(10), c = runif(10)) sink() and would want to add some header information, like /* created on 31.3.2011 */ /* author */ /* other redundant information */ How would I add this "header"? Doing it manually seems trivial. Hit a few Enters, copy/paste or write information and you're done. Of course, in R, I could read in example.txt , create example2.txt , add header information and then example.txt . I was wondering if

问题 I'm just wondering if there's a way to locate numbers on a page with jQuery or plain Javascript. Here's what I want to do: Say "June 23" is on the page. What I want to do is be able to prepend and append some <span> selectors to the number. Using :contains() with jQuery selects the whole thing, not just the number. These strings are being generated without any wrapping elements by a Wordpress theme I'm working on, and I only want to select the number . Any help would be appreciated! Thanks

问题 List has 2 methods that are specified to prepend an element to an (immutable) list: +: (implementing Seq.+: ), and :: (defined only in List ) +: technically has a more general type signature— def +:[B >: A, That](elem: B)(implicit bf: CanBuildFrom[List[A], B, That]): That def ::[B >: A](x: B): List[B] —but ignoring the implicit, which according to the doc message merely requires That to be List[B] , the signatures are equivalent. What is the difference between List.+: and List.:: ? If they

问题 I've a method that has as an argument v ...interface{} , I need to prepend this slice with a string . Here is the method: func (l Log) Error(v ...interface{}) { l.Out.Println(append([]string{" ERROR "}, v...)) } When I try with append() it doesn't work: > append("some string", v) first argument to append must be slice; have untyped string > append([]string{"some string"}, v) cannot use v (type []interface {}) as type string in append What's the proper way to prepend in this case? 回答1: append(

问题 I want to add a div as a first element using jquery on each click of a button <div id='parent-div'> <!--insert element as a first child here ...--> <div class='child-div'>some text</div> <div class='child-div'>some text</div> <div class='child-div'>some text</div> </div> 回答1: Try the $.prepend() function. Usage $("#parent-div").prepend("<div class='child-div'>some text</div>"); Demo var i = 0; $(document).ready(function () { $('.add').on('click', function (event) { var html = "<div class=

问题 I'm trying to append a line of HTML before all the children of the body . Right now I have this: // Prepend vsr-toggle var vsrToggle = document.createElement("div"); vsrToggle.innerHTML = "<input type='checkbox' name='sr-toggle' id='srToggle'><label for='srToggle' role='switch'>Screen reader</label>" document.body.insertBefore(vsrToggle, pageContent); It's working fine because the HTML is being added to the created div . However, I need to prepend this element without wrapping it in a div. Is

问题 Arrg! My site (in progress) is working great so far in all browsers I've tested to-date (firefox, safari, chrome, and IE8) but not in IE7 (I dont know about IE6 or other browsers) .... I'm not positive but i think the issue has to do with the use of prepend() in my jQuery. the main issues are the main menu (should show up in the blue horizontal bar to the left of the logo) as well as the search box at the top right, both added using prepend. there are other issues throughout in IE7 so i'm not